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ESTIEM Lean Six Sigma Green Belt course - Glossary of terms


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ESTIEM Lean Six Sigma Green Belt course - Glossary of Lean Six Sigma terms

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ESTIEM Lean Six Sigma Green Belt course - Glossary of terms

  1. 1. Lean Six Sigma Glossary for publication
  2. 2. 1 Item Description ABC Activity Based Costing. ABC is a business improvement process used to streamline cost for work activities by more realistically measuring the costs of products, and processes through the detailed evaluation of the value-added work performed in activities. Abscissa The horizontal axis of a graph used to plot an “X” variable. Acceptance Region The region of values for which the null hypothesis is accepted at a given confidence level which is related to the chosen sample size (alpha risk). Action Plan A plan to implement a change or a project that identifies the target to be achieved, the milestones for achievement of this result, the individual assigned responsibility for the project, the steps that will be taken and indicators of both the interim progress toward the goal and the achievement of the desired result (in Hoshin Kanri this is called an Implementation Plan) (See HOSHIN KANRI). Activity An identifiable work unit that combine together to form a process. Activities normally are confined in location and each activity may be further sub-divided into the tasks that are performed by individual participants or teams within the activity. Affinity Diagram A thinking tool used to gather information or viewpoints, define a situation, generate ideas, sort the ideas into coherent groups, and classify these groups with clear labels. Alpha Risk The probability of accepting the alternate hypothesis when, in reality, the null hypothesis is true. This factor is usually designated by the Greek letter alpha (α). Alternative Hypothesis A tentative explanation which indicates that an event does not follow a chance distribution; contrast with the null hypothesis and considered an alternate opportunity (H1). Andon [Japanese] From the word meaning ‘light’ – a visual control device to indicate production process status – it may be either a flashing light that signals problems (e.g., yellow for off-rate production and red for line stoppage) or it may be an overhead video display that provides visual and numerical indicators of flow in production. An andon is used to describe the current status of production and to alert everyone to changes in status or emerging problems (line slowdown, etc.). ANOVA Analysis of Variance. A statistical method used to evaluate if there is a statistically significant difference among means of similar groups. A method of determining which factors in an orthogonal array significantly affect the response by comparing response variation between factor levels to error variation within factor levels. Results of an ANOVA are frequently utilized to establish an analytical model. Architecture The top-down structure of a system. Business architecture typically represents the decomposition of business processes into a system of work processes that deliver the overall results.
  3. 3. 2 Assignable Cause A source of variation in results which is non-random (it can be assigned to a particular cause or reason for occurrence); a change in this factor (“Vital Few” variables) will produce a significant change of some magnitude in the response (dependent variable), e.g., a correlation exists; the change may be due to an intermittent in-phase effect or a constant cause system which may or may not be highly predictable; an assignable cause is often signaled by an excessive number of data points outside a control limit and/or a non-random pattern within the control limits; an unnatural source of variation; most often economical to eliminate. Attribute A quality or characteristic feature of a person, place or thing. Attribute Data Qualitative data that can be counted; factual information at the nominal level; subdivision is not conceptually meaningful; data which represents the frequency of occurrence within some discrete category, e.g., 42 solder shorts. Authority A person who has been granted the right to make a decision, issue a command, control, or settle a dispute without reference to a higher-level authority. Autonomation A form of automation in which machinery automatically inspects each item it produces for defects and then stops production if a defect is detected and notifies the operator of this condition (see jidohka). Autonomous Maintenance The self-management of routine equipment maintenance tasks by the operators. This approach may also include participation of operators in the repair and service of their equipment. Baka Yoke [Japanese] A manufacturing method for preventing mistakes by designing the production process, equipment and tools so operations cannot be performed incorrectly. In this system the device not only prevents incorrect operation, but it also provides a warning to the operator of incorrect performance (see POKA YOKE). Bar Graph This graph visually compares bars that indicate the magnitude or accumulated frequency count of an attribute the using the relative length of bars to illustrate differences for a common measurement scale of the data. Baseline Either an historical or current level of performance that is used as a standard of comparison for future performance improvements. Balanced Production A manufacturing condition where the capacity of the production resources is matched exactly to the market demand for the product. Work is distributed in the production line to avoid underutilization or overburden of individual activities and assure a shorter flow time as both bottlenecks and downtime are avoided. Batch and Queue Producing more than one unit of production at a time and then moving the units to the next operating step before it has a need to produce using these units. This style of production creates waiting time as parts are moved in batches and wait in queues for the next operation to be conducted. Bayesian Analysis A decision-making method used to estimate the probability that an outcome will occur when a known prior event occurs. It applies the probability equation known as Bayes’ Theorem. Benchmarking A method to establish targets and identify improvement projects based on the comparison of processes with leading best practices. Beta Risk The probability of accepting the null hypothesis when, in reality, the alternate hypothesis is true (the null hypothesis is false). This factor is noted by the Greek letter beta (β) (See CONSUMER’S RISK and POWER OF THE TEST).
  4. 4. 3 BIC Best-In-Class. The top performing organization in a group of similar organizations as indicated by performance for a measure or process characteristic in a benchmarking study. BIC usually requires that an organization’s process measure in the top 5th quartile of the process benchmark results. Bottleneck The step in the production process that restricts the smooth flow of output to the customer – a production resource whose capacity is equal to or less than the demand that is placed upon it is a bottleneck. Breakthrough A dramatic change in process performance which removes an old barrier or surpasses milestone performance by achieving a significant increase in efficiency, cost reduction, quality level or some other measurable performance indicator (see KAIKAKU). Brainstorming A creative process for bring out the ideas of team members regarding a specific topic. The problem to be considered must be clearly defined. Each person presents their ideas without critique by others. Ideas are recorded without discussion, but people are encouraged to creatively build on the ideas of others. Breakthrough Improvement in performance to an unprecedented capability level for a service, product or process (or a similar dramatic reduction in defects, cost or cycle time); also the process of achieving a vision (desired business state) that is a significant departure from the current business state (current state). Business Excellence A model for developing “aspirations” for quality by indicating areas that must be addressed by processes, measures, action, or reviews in order for an organization to achieve long-term results driven by a focus on customers and significant stakeholders. The approach to business excellence is embedded in the programs of the Malcolm Baldrige National Quality Award and the European Quality Prize of the European Foundation for Quality Management. Business Process The end-to-end sequence of processes and activities that defines one or more business functions that are required to deliver a product (either goods or services) to a customer. If the customer is an external customer then these processes may be considered to be core business processes, if they serve internal customers, then these processes may be called support services. Cascade The successive top-down deployment of training or strategy where a manager leads his subordinates who thereafter lead their subordinates in the deployment of a business initiative through training or an active learning process. Catchball The give-and-take dialog that occurs between organization levels as part of the negotiation process that leads to shared objectives or consensus on direction in a policy deployment planning system (also called “cascade push-back”); part of a Hoshin Kanri planning system. Capability The inherent potential of a machine or process to produce goods or services that meet specified requirements. Its ability to meet these requirements must be demonstrated by measured performance in a process capability study (see Cp and Cpk). Cash Flow A financial term that designates the balance between cash inflows (receivables) to a business and cash outflows (expenditures). Causality The principle that every change implies the operation of a cause. Cause That which produces an effect or brings about, creates or serves as a catalyst for change – when a cause occurs, then the effect is created in a predictable manner.
  5. 5. 4 Cause-Screening A process for evaluating problem symptoms and sorting them into apparent causes, then sorting these into potential causes in order determine the root cause (see ROOT CAUSE ANALYSIS, DIAGNOSIS). Cause and Effect Diagram Often referred to as an Ishikawa Diagram (to respect its originator Karou Ishikawa) or a fishbone diagram (due to its shape), the Cause and Effect Diagram illustrates the linkage between a problem statement and its potential causes which may be designated by a set of categories called the “6 M’s” (Man, Machine, Measurement, Method, Manpower, and Mother Nature). Cell An arrangement of people, machines, material and equipment so that processing of the production unit are co-located in their sequence of operation with minimal delay time between process steps. Central Tendency Numerical average, e.g., mean, median, and mode; center line on a statistical process control chart. Chaku-chaku [Japanese] ‘Load-load’ – a method of conducting single piece flow (nagara) in which the operator moves from machine to machine taking the part from a previous machine and loading into the next machine to decrease the inter-machine waiting time. Changeover The act of converting a production line or equipment to produce a new part, product, or model and which may require a new setup of the facilities such as changing of tooling, material replacement or rearrangement of people and equipment. Changeover Time The time required to convert a workstation to achieve a part, product or model changeover – it includes teardown time to remove a previous set of production conditions and setup time to assemble the new production conditions (see setup time). Characteristic A definable or measurable feature of a process, product, or variable. Charter A written commitment (or contract) by management that states the purpose and objectives of a project improvement team. Resources and performance targets are specifically addressed, participants are assigned responsibility and review authority is established. Check Points (Control Points) A physical point in a process where an adjustment can be made to affect the throughput rate, quality level, or test the in-process work for adherence to requirements. This point may also correspond to a process constraint or choke point. Checklist A predefined document with a series of steps that must be followed in order to carry out an operation properly. It contains a description of activities that must be done broken into the component parts that must be approved (or checked off) as they are completed. Checksheet A tally record of observations that can be used for purposes such as data collection, problem analysis or testing. Constraint Anything that reduces the capacity of a system from achieving its throughput capability – the bottleneck that most severely restricts the continuous flow of production. Consumer Any individual who is an ultimate user of the goods or services of an organization. Consumption may be either physical or mental as the products may be tangible or intangible. Continuous Flow The production process where units are produced sequentially moving one unit at a time through the processing steps. Continuous flow is also called one-piece flow or single-piece flow production (see nagara).
  6. 6. 5 Classification A way to differentiate between variables, factors, or functions based on their logical categories that define their associations or relationships. Common Cause Variation See RANDOM CAUSE Confidence Level The probability that a random variable “x” lies within the physical interval defined in the data for probability of occurrence. Confidence Limits The values that define the margins or physical range of a confidence interval for a chosen probability or confidence level. Consensus A state of agreement within a team or group where everyone supports an action or decision as the best choice, even if some don’t fully agree with it. In arriving at this point, all arguments and data that show counter-points have been reviewed and considered in arriving at the final agreement. At the end, everyone openly participates, understands, and supports the decision or action. Consumer’s Risk Probability of accepting a hypothesis when, in fact, the hypotheses was false and should have been rejected (see BETA RISK). Continuous Data Numerical information that is either interval or ratio data; where its subdivision is meaningful; and all numbers in this interval specify a natural meaning; data observed from a scalar continuum Continuous Improvement A method that assures the step-wise or incremental improvement of a process or the sequential improvement in the performance of a product’s features over time based on the idea that performance improvement is necessarily a continuous activity to ensure ongoing customer satisfaction and improved results (see KAIZEN). Control Chart A graphical rendition of a characteristic’s performance across time in relation to its natural control limits and central tendency which is used to evaluate if a process is operating in a state of statistical control Control Limits Statistical criteria for either taking action or judging the significance of variations between samples or subgroups. Upper and lower control limits are calculated based on the capability of work process as judged by their standard deviation Control Specifications Specifications that define the acceptable limits for a product being manufactured. COPQ Cost of Poor Quality. (Also called the price of non-conformance IPONC) or the cost of non-quality (CNQ), or just the cost of quality (COQ)). These costs are calculated as the sum of cost for preventing problems, detecting problems, and correcting observed internal and external failures. The cost of prevention is an investment to reduce the other costs. COPQ is often off-set by the return on quality – the benefit received from reductions in scrap, rework and lost time, as well as a productivity improvement from using the failure time to produce additional products Cost of Ownership The total cost associated with an acquisition: including the initial purchase price, plus additional cost such as cost of quality assurance or compliance testing, cost of receiving inspection, cost of reliability tests, cost of warehouse storage, cost of warranty, cost of field failure, cost of maintenance, etc. Represents a total life cycle cost. Correlation A measure of the degree of strength in the association between two variables (also related to Pearson correlation coefficient, coefficient of determination, and
  7. 7. 6 R2 statistic). Cp This capability index indicates the ratio between a product’s specifications (planned tolerances) and the process capability or spread (natural tolerance or variation in the production process). To be calculated, the process must be in statistical control (e.g., no special cause variation has been observed in the data) (see PROCESS CAPABILITY) CpK This capability index extends the measurement beyond the Cp by taking into account both process centering and dispersion (or accuracy and precision). The measure compares the upper and lower specification limits to the average of the observed process data. When Cp and CpK are equal, this means that the process is centered at the nominal value of the product specification and the magnitude of the ratio describes the match of the performance with the specification (values over 1.0 indicate that there is more than a 95% confidence in meeting the specified level of performance (see PROCESS CAPABILITY). Cross-Functional Team A team who membership is composed of participants from several different functions that have an interest or “stake” in the outcome of a particular activity. These functional groups may act as “process owners” for an improvement project that has been assigned to a team through the project chartering process. Customer The person who receives the output of an activity. This may be an economic customer (purchasing goods or services), an investment customer (providing capital for the business), or an internal customer (providing process output to the next step in the process). Customer Expectations Those characteristics that the customer would like to have delivered as the output of your process or business activity. Customer Focus The concept that top priority must be given to working on those things that satisfy the short and long-term customer needs. All decisions must be made in full understanding of their impact on external customers. Some organizations also extend this principle to their internal customers Cycle Time The time required to complete a cycle or sequence of production operations from start to finish. The elapsed time from when an item first starts in an activity or process through the time it is received by the customer of that activity or process step. This includes the time for set-up of the work, time for transaction processing, and logistics time associated with shipment and handling in the process. When cycle time for each operation is equal to or less than takt time then products can be produced in a single-piece continuous flow. Daily Management The process of managing and performing the routine work of an organization as accomplished by front-line workers to achieve the organization’s basic mission (see NICHIJO KANRI). Dantotsu [Japanese] Being the ‘best of the best’ – sometimes translated as “world class” or best practice Data Factual information used as a basis for reasoning, discussion, or calculation; often refers to quantitative information Data Collection The process of gathering raw product or process information about its performance by making observations, recording measurements, and transferring these observations into a structured format Defect An unacceptable variation in a quality characteristic from its desired level of
  8. 8. 7 performance Defective A unit of product or service that contains at least one defect which causes the unit not to fulfill a specified requirement. Deming Cycle See P-D-C-A Dependent Variable A response variable that is predicted by an experiment; e.g., Y is the dependent or “response” variable when Y= f (X1 … Xn). DFM Design for Manufacturability. The process of developing a product design that considers the method in which it will be produced and is optimized to be assembled efficiently and effectively by workers in a process for which it was explicitly designed Diagnosis The activity of discovering the cause(s) of deficiencies. The process of studying symptoms, taking and analyzing data, conducting experiments to test theories and then establishing the relationships between causes and effects (see CAUSE- SCREENING, ROOT CAUSE ANALYSIS). Distribution In statistics, the manner in which large numbers of observations tend to group themselves around some central value with a certain amount of variation on either side of the central value. Many distributions are defined using a mathematical relationship that is defined by the measure of central tendency and variation or “scatter” on either side DOE Design of Experiments. A designed experiment discovers optimized conditions when there are two or more independent variables and possibly several dependent variables, with a sharply reduced number of experimental runs over a One-Factor-At-a-Time (OFAT) approach to the same problem. The method of scientific discovery. Downtime Any loss in production time due to equipment operating capability resulting from breakdown, maintenance or repair, power failure, operator availability, etc. (see operational availability and uptime). Driving Forces Forces that change a situation by moving the outcomes toward the desired direction or future state of performance DTC Design-to-Cost. Developing a product design based on an allowed or budgetary price of the future product, as allocated to the sub- assembly, module, or part level of the product’s bill of materials Effect An observable action, result or evidence of a problem. Empowerment The act of placing accountability, decision-making authority and responsibility for the performance outcomes of work at the lowest possible level. The extent to which a person is empowered depends on personal capabilities and seriousness of the consequences. Entitlement The best performance results obtainable without adding additional resources. In fact, an organization requires fewer resources to operate at entitlement than it does at baseline, because it is not performing corrective actions to increase the performance to this level. Error When an individual makes an inadvertent mistake, this mistake is compounded to become an error when the product of their work is passed on to the next phase of a process and thus has an impact on the productivity of subsequent steps inside the organization. If an error is not caught within an organization and it “escapes” to the customer, then that error becomes a defect
  9. 9. 8 Error-Proofing Any process to prevent errors from moving down the production line and being delivered to customers as defects. When errors are not passed down the line, then both quality and productivity improve (see baka-yoke and poka-yoke FPY First Pass Yield. The percentage of production that completes the final quality test for performance without being scrapped, rerun, reworked, retested or returned or diverted for off-line repair (also called the Right the First Time Yield (RFTY) or outgoing quality level). Experiment A structured investigation or test that is conducted under defined conditions to determine an unknown effect; to illustrate or verify a known law; or test to establish a logical hypothesis. An experimenter selects and controls specific factors to study their response on a specific characteristic. Experimental Combination Settings (or levels) of all factors for one run of the planned experiment. The full set of experimental combinations is known as the treatment combinations of the experiment. Experimental Design The arrangement in which an experiment is to be conducted. It includes the selection of the type of experiment to be performed as well as the spread in levels for the factors and the sequence of the combinations used in the experiments Experimental Error Variation in measured observations of experimental outcomes that made under identical test conditions that indicate the effectiveness of the experimental system. This is also called residual error. The amount of variation which cannot be attributed to the variables included in the experiment. The total amount of experimental error can be observed in the variation of the center points in a central composite designed experiment. Experimental Factor (“X”) that is managed under an An independent variable experimental plan to control its changes and determine the influence that it has on the dependent variable (“Y”). Facilitator This is the title given to a person who functions as a coach, teacher, or moderator to make the work of a group, team or organization easier. In quality improvement teams, the facilitator focuses a team on their group process, while the team leader concentrates on the content. Feedback Direct inputs from customers about their satisfaction with the progress or operation of a process. Fire-Fighting The act of eliminating the immediate symptoms of problems by removing sporadic causes of quality problems and restoring the status quo. This corrective action process is followed by a long-term analysis to eliminate the root cause of the problem and execute permanent preventive action so the problem does not recur. Fishbone Diagram See CAUSE AND EFFECT DIAGRAM. Fixed Effects Model Experimental treatments are specifically selected by the researcher. Conclusions only apply to the factor levels considered in the analysis. Inferences are restricted to the experimental levels.
  10. 10. 9 Flow Chart A block diagram that illustrates the sequential actions and decisions that represent the steps of a process. This chart may follow a logical, geographical, physical or functional means to decompose the process (break it down into smaller steps or activity increments). FMEA Failure Mode and Effects Analysis. A formal method for both anticipating and prioritizing possible failure modes of a new or modified design, work procedure or process step; and implementing preventive or control procedures prior to the observation of a failure (mistake-proofing). A method that can be used for either engineering change or a business process change. Force Field Analysis An analysis tool that contrasts the positive (helping or driving) and negative (hindering or restraining) forces that are influencing a desired change. This method illustrates areas of resistance in an organization as well as areas of opportunity for the rapid promotion of change Frequency Distribution The pattern or shape formed by the group of measurements in a distribution. Functional Team A team whose membership consists of participants from a single business area or function (compare this definition with CROSS- FUNCTIONAL TEAM). Gage Accuracy The difference between an observed measurement average of a gage and the master average of the same parts using both precision instruments and a measurement standard. Gemba[Japanese] The shop floor or workplace where production operations occur. Gantt Chart A planning method used to indicate projected start and completion time for scheduled activities that result in the accomplishment of an overall project. Golden Thread The act of following the logical linkage (golden thread) from a problem statement to its root cause in order to resolve it. Hanedashi[Japanese] Automatic part ejection. Heijunka[Japanese] A method for load leveling of production rate or line balancing to smooth the flow of production by avoiding batching of different product categories, mixing production processes or fluctuating volume produced for the same product Hinshitsu Kanri[Japanese] Quality control management system. Histogram Vertical display of a population sampling distribution that shows the frequency of occurrence; a formal method of plotting a frequency distribution. Homogeneity of Variance The variances of two or more groups are contrasted to test if they are equal (a test for statistical differences in variation). Hoshin Kanri[Japanese] Strategic planning and business control system that assigns the resources, people to complete projects that achieve breakthrough on the focus areas for improvement and achieve measurable goals for performance gains.
  11. 11. 10 Hypothesis Test A test of difference between two hypotheses, a null hypothesis and an alternative hypotheses (see NULL HYPOTHESIS and ALTERNATIVE HYPOTHESIS), where the comparison is made based on a specified degree of risk (see ALPHA RISK and BETA RISK) in order to achieve the desired confidence in the finding. The validity of the test depends on the underlying statistical distribution (see TEST OF DIFFERENCE), capability of the measurement system, and the size of the sample that is used for testing (see OFAT). Independent Variable A controlled variable that is expected to change the results in an experiment as measured by a dependent variable; a variable whose value is independent of the value of another variable; independent factor whose value is managed using a system of experimental controls (the “X” variable when Y= f (X1… Xn). Innovation The act of converting a creative concept into a concrete or tangible product or output. The creative destruction of the past or the planned abandonment of familiar ways of working (according to the late Austrian economist Joseph Schumpeter). Insight The processing of intelligence to formulate the underlying meaning of the facts observed. Insight may be extended to become foresight if future trends may be projected or predicted based upon observed past behaviors. Instability Unnaturally large fluctuations in a pattern of natural variation that is not predictable. Intelligence The understanding that comes from dedicated study of conditions that influence the business environment of an organization: market, technology, competitors, etc. Good intelligence provides a sound understanding of factual conditions that prevail in the world (see also insight). Interaction The tendency of two or more variables to produce an effect in combination which neither variable would produce if it were acting individually. The effect of one factor depends on the settings of another factor (e.g., when the effects of a factor A are not the same at all levels of another factor B). In other words, interaction exists if two factors have different outcomes as they are combined in different ways. Interrelationship Digraph An tool that allows a team to systematically identify, analyze and classify cause and effect relationships that exist among all critical issues so that key drivers can be identified. Interval Data A category of numeric data that has equal units of measure but no absolute zero point, i.e., quality scale or index. Interview The process of conducting a survey or asking individuals a set of prepared questions to gather data about a topic Jidohka[Japanese] Transferring human intelligence to automated machinery so machines are able to detect production of a single defective part and immediately stop production and request help. In Toyota this also includes the responsibility of each operator to inspect the quality of their own work and when a problem is detected to stop working until the cause of the defect has been corrected. Jundate[Japanese] A sequential supply system for production parts replenishment.
  12. 12. 11 Kaikaku[Japanese] Radical improvement of any business activity to eliminate waste by reorganizing process operations to achieve dantotsu breakthrough results (see HOSHIN KANRI). Kaizen[Japanese] Continuous, incremental improvement – always doing little things to consistently set and achieve higher work standards of performance. Kanban[Japanese] A signal that authorizes production or movement of a product using a card, sign board, container, or other physical indication to control the flow of production material through the process Knowledge The intellectual, mental understanding of information and their relationships that is acquired and retained through both study and experience. Lagging Indicator A performance indicator that specifies after-the-fact what occurred in the period of observation. This type of indicator has explanatory value. Leading Indicator A performance indicator that anticipates future results based on its current values. This type of indicator has predictive value Lead Time The total time a customer must wait from submitting an order to receiving the ordered item (see order turnaround time). Lean A systematic approach to identifying and eliminating waste (non- value-added activities) through continuous improvement by making the production flow according to the rate of pull by the customer demand. Lean maximizes production of products to be sold to customers while minimizing operating and inventory costs. Level A particular setting for a factor. Line Balancing A process for distributing work in a production line so that tasks and staff are evenly balanced to coordinate individual work station cycle times to meet the takt time (see takt time). Line Charts Charts used to track the performance without relationship to process capability of control limits. Little’s Law Named after MIT Professor John D. C. Little who is considered the father of queuing theory in operations research – the average number of customers in a system (over some time interval) (work in process) is equal to their average arrival rate (throughput), multiplied by their average time in the system (cycle time). Lower Control Limit A horizontal dotted line plotted on a control chart that to show the lower process limit capability of a process, the calculation will be an approximation of three standard deviations below the grand average for the performance measure Main Effect A comparison of the responses at each level of a factor averaged over all levels of other factors in the experiment. Management System A series of activities that are used to plan, direct, control, organize, communicate, and report the behaviors organization. Measurement A process-level, actionable indicator that directly translates into work activities of individuals or teams (e.g., throughput rate, work- in-process inventory, job accident rate, billing inquiry rate, etc.).
  13. 13. 12 Metric A system-level, aggregate indicator of overall business performance (e.g., return- on-assets, employee satisfaction, customer satisfaction, etc.). Mental Model A simple model defining the structure of a process at a high level of logical abstraction, rather than at a level of detail that is required to conduct the process work (e.g., SIPOC Map). Minomi[Japanese] Supply Mission A statement that succinctly defines the purpose, role, and ‘reason for being’ of an organizational unit and specifies the relationship or contribution that this unit has to the entire structure. Mixed Effects Model A designed experiment that contains elements of both the fixed and random effects models. Muda[Japanese] Waste – all (non-value added work) of those elements of production that add no value to the product or service but only increase its cost. Multi-Voting A structured voting process used to reduce a large number of items, usually ideas, to a more manageable number for more processing or analysis. Mura[Japanese] Waste – all (unevenness or variation in work) irregularities that sometimes happen in a production schedule or in the volume of parts or finished goods. Muri[Japanese] Waste – all (overburden) work that overloads or creates a burden on the workers to produce at the point of activity on the shop floor (gemba). Nagara[Japanese] One-piece production flow. Nichijo Kanri[Japanese] The daily management control system implementing 5S, visual controls, and standardized work. This system is monitored using fundamental measures of quality and cycle time to assure balanced flow of production to reliably meet customer demand. NGT Nominal Group Technique. A structured idea-generating method that is used to develop, combine and prioritize a list of individual solutions (or other idea category) using a voting technique where each of the participants receives an equal number of votes (number of ideas divided by 3 is a good rule). Non-value Added Activity Any activity for which a customer would not willingly pay and has no need. These activities add no real value to a product or service and are a form of waste (e.g., waiting time, transportation and handling time, or repair time) (see value). Nominal A category of data that is unordered where values indicate either membership or non-membership in a category with no implication of quantity, i.e., assembly area number one, part numbers, etc. Non-Conforming Unit A unit of production which does not conform to one or more specifications, standards, and/or requirements. Nonconformity A condition within a unit which does not conform to some specific specification, standard, and/or requirement; often referred to as a defect; any given nonconforming unit can have the potential for more than one nonconformity.
  14. 14. 13 Normal Distribution A curve that follows the mathematical definition of a Gaussian frequency distribution – continuous, symmetrical density function characterized by a bell- shaped curve, e.g., distribution of sampling averages. The normal distribution is the basis of statistical concepts used throughout statistical process control as well as many statistical tests, procedures and techniques. Many observations in nature follow the normal distribution. Null Hypothesis A tentative explanation that indicates that a chance distribution is operating and labeled as H0to indicate its status as the null hypothesis; stands in contrast to the alternative hypothesis (H1). NVA Non-Value-Adding. Activities or tasks that do not contribute to meeting customer requirements and are candidates for elimination from the work process without degrading its overall results or performance. These are activities that the customer is not willing too pay for, given they had a choice. One-Piece Flow The opposite of batch production. Instead of building several products and holding them at the work station before passing them on to the next operation, the operator passes each product to the next station without interruption of the production flow and the products are presented one-piece-at-a-time to their subsequent process (see continuous flow and nagara) One-Sided Hypothesis Test A hypothesis test which evaluates the value of a parameter for either the upper bound or the lower bound (greater than or less than), but not both tails at the same time (test of equality or inequality). One-Touch Changeover The reduction in work change over or set-up time so that the task is completed in a single step (see Single Minute Exchange of Dies). Operational Availability (Ao) The percentage of time during which production equipment is available to operate – also called uptime. It is calculated as machine operating time as divided by available time (net planned non- working time for training, breaks, vacations, or holidays) (see uptime and downtime). Operational Definition A precise description of a term (process, product, etc.) that is decomposed into its logical sub-groups according to clear boundary conditions for each group with a specified means to measure and evaluate each sub-group specified within the definition. Operational Excellence The state of organizational operation where work is performed in a manner that is most efficient and effective and at the lowest total cost (this may include the external costs borne throughout the life cycle of use for the product or service delivered by the organization as an output). Ordinal Ordered categories (ranking) with no information about distance between each category, i.e., rank ordering of several measurements of an output parameter Ordinate The vertical axis of a graph used to plot a “Y” variable. OTAT: Order Turnaround Time. The total time from initial placement of a customer order to delivery of the ordered item in a usable state.
  15. 15. 14 Out of Control The condition where a process has variations that fluctuate outside the computed control limits. This condition normally indicates that the process is not operating as desired or that external factors have been introduced to change the way the process performs. A process that is in this condition is not stable and therefore is not predictable . Parameter A constant defining a particular property of the density function of a variable. Pareto Analysis A technique for ranking potential problem contributors by their relative quantitative contribution to a whole problem and to separate the vital few potential causes from the trivial many. This method is named after the 18th century Italian economist Wilfredo Pareto. Parking Lot A list of topics that have been postponed for discussion at a later time with the consent of team participants. The reason for delay on discussion about these topics is that they are not immediately relevant to the discussion, but warrant dialog at a future time. Partitioning A way for structurally decompose a problem, situation, or opportunity according to the elements that contain a team’s cultural frame of reference and dividing these into a set of underlying assumptions which the solution must overcome. P-D-C-A Cycle Plan-Do-Check-Act or ‘Deming Cycle.’ The continuous improvement cycle that is alternative named after Dr. W. Edwards Deming or Walter A. Shewhart. In reality the name was developed by members of the Japanese Society for Quality Control in the late 1950s as they sought to simplify the idea of an improvement cycle that was presented by Deming. PDCA is a structured, cyclical (step-by-step logical process) methodology for developing and implementing actions of any type: Plan for action by collecting and analyzing data and developing alternatives; Do, implement the selected alternative on a small scale to pilot the change; Check, evaluate the results and compare with expected values; Act, by adopting or abandoning the change, standardize the action, and look for the next improvement opportunity. Perturbation A nonrandom disturbance. Pie Chart A pie chart visually shows the proportional relationships of logical sub-categories within a large data set. Pitch: The pace and flow of production – the amount of takt time it takes to produce a single, shippable unit of production (see takt time). Poka Yoke [Japanese] A Japanese term translated as mistake-proofing, fool-proofing and safeguarding. This method applies a discipline of simple, low-cost methods to either prevent mistakes or to detect them immediately and request a corrective action before the mistake can be repeated and problems escape to customers. Mistake- proofing techniques are used to avoid, eliminate, and/or prevent errors at the point of process design. The method uses devices and detection methods to identify inadvertent mistakes and prevent them from occurring. Mistakes are activities that are wrong at the point of occurrence (within operation activity); errors are mistakes that have been passed on to the next workstation and reduce its productivity; and defects are errors that have failed detection in the process and are delivered to the customer (see ERROR-PROOFING and BAKA YOKE).
  16. 16. 15 Policy Deployment The process for cascading shared goals into a common set of objectives and measurements that are aligned across functional boundaries throughout the entire organization. Population The totality of all units or members in a group of similar items from which a sample is drawn. This is also referred to as the universe or domain of a performance indicator. Power of the Test The probability of rejecting the null hypothesis when it is false and accepting the alternate hypothesis when it is true. This is calculated as 1 – β (see BETA RISK and CONSUMER’S RISK). Precision The relative spread among the elements of the data sample which is measured as variation (e.g., range, variance, or standard deviation). Prevention The practice of eliminating unwanted variation of priori (before the fact), e.g., predicting a future condition from a control chart and when applying corrective action before the predicted event transpires. Prioritization Matrix A matrix that illustrates the performance of various decision options (left column) against a set of weighted criteria for the decision (top row). Summary calculations for each of the options are presented in the right-hand column. Probability The chance of something happening; the percent or number of occurrences over a large number of trials. Probability is usually indicated as a number from 0 (no chance of an event occurring) to 1.0 (absolute certainty of an event occurring). The range of values between these limits is described as a probability distribution (e.g., uniform, normal, or Poisson distribution). Probability of an Event The number of successful events divided by the total numbers of trials. Problem A deviation from a specified standard or desired state. A gap in the level of performance between the current state of operation of a process and its desired state (or target value – whether the target is set by plan, budget, or engineering calculation) for that measure. Problem Solving A process of solving problems; the isolation and control of those conditions that generate or facilitate the creation of undesirable symptoms. A problem is considered solved when the root cause of the problem formation has been removed. Problem Statement A succinct statement of a problem that describes what the problem is, where it occurs, when it occurs, some potential reasons why it occurs, how the process operates at the point of this problem, and who is involved in the problem or in a potential solution. Process A particular method of performing work or accomplishing a task, generally involving a number of activities, steps or operations. A work process is characterized by its inputs; control mechanisms that direct its performance (e.g., give signals to start or stop and perform its critical functions); resources that are applied to accomplish the specified transformation that occurs in the sequence of activities or steps; and outputs that are delivered. Inputs are said to come from suppliers of the process and outputs are delivered to its customers (see also SIPOC MAP). Process Average The central tendency of a given process characteristic across a given amount of time or a specific point in time.
  17. 17. 16 Process Capability A ratio of the “voice of the process” to the “voice of the customer” that measures the process variability relative to the customer’s specification and the nominal or target value for performance. These ratios relate customer requirements to actual process performance (see also Cp and Cpk). Process Control See STATISTICAL PROCESS CONTROL Process Control Chart Graphs upon which plotted data observations against the specific statistical process control limits to record the process behavior as a means for improving or controlling the performance of the activity. Process Model A block diagram that illustrates the flow of a particular work or business process and illustrates the boundaries of the process, it’s major inputs and outcomes delivered. It may also be decomposed from the process level to a activity level and then further broken down into the task level Process Spread The range of values which a given process characteristic displays; this particular term most often applies to the range but may also encompass the variance. The spread may be based on a set of data collected at a specific point in time or may reflect the variability across a given amount of time. Process Touring Also called Management by Walking (Wandering) Around (MBWA). The act of walking a process from end-to-end as if it was a fresh experience – taking a naïve perspective – looking at it with the eyes of a first-time tourist. This process is very distinct from a software structured walkthrough which is used for analysis and assessment of software quality. In the case of the later the “touring” has a plan that is followed rigorously, while in the former case MBWA takes a more casual agenda for its examination of activities. Producer’s Risk Probability of rejecting a lot when, in fact, the lot should have been accepted (see ALPHA RISK). Production Status Board An electronic status board that displays production information such as hourly targets and units produced. Information about problems and abnormal conditions relating to continuous flow are recorded for visual observation by the entire workforce. Productivity A measure of process outputs given the rate of production inputs (or result divided by effort). Only product that meets specification should be included in the calculation as output as product that does not conform will require additional work which degrades the level of productivity. Pull System A system of production scheduling whereby the demand for production is set by the withdrawal of a finished item from inventory by a customer order, thereby setting a signal to replenish this item in inventory by producing an additional unit (this produces the trigger signal for a one-piece production flow). Project A temporary activity undertaken to create a unique task that requires coordination and planned action. QCO Quick Changeover. The ability to change either the product or model rapidly on a production line – switching tooling and fixtures rapidly so that multiple configurations or products may be produced using the same resources (see Single Minute Exchange of Dies and One-Touch Changeover). Quality The ability of a process or product to consistently meet or exceed the expectations of its customer. The entitlement of value that a process should expect if it is operating as designed.
  18. 18. 17 Quality Assurance Sometimes abbreviated as QA. This quality management activity involves activities in the business, systems and technical audit areas. A set of predetermined, systematic actions that are required to assure that a product or service satisfies or is able to meet its quality requirements. Quality Control Sometimes abbreviated as QC. This quality management activity is a regulatory process by which actual performance is measured, compared with standards, and act upon the differences. This is used to differentiate between inspection and test activities and other quality-related tasks. Quality Engineering Sometimes abbreviated as QE. This quality management activity provides the means to design quality into products, services, and processes by applying measurement systems analysis, statistical analysis, process control, and standard operating procedures. Quality Improvement Sometimes abbreviated as QI. This quality management activity is a planned, systematic improvement through either small, incremental improvement projects (kaizen) or by major, breakthrough projects (hoshin) to move quality indicators toward the level of their process entitlement Quality Indicator A measure or metric that indicates the desired performance of a product or service from the perspective of a customer. A specification may be set for the quality indicator to assure that a nominal performance output level is established and maintained. Quality Management Sometimes abbreviated as QM or, as it is frequently called Total Quality Management (TQM). This process provides an organization structure, operating philosophy and systematic methodology for the delivery of quality engineering, quality control, quality assurance, and quality improvement through a formalized quality system. QM is sometimes divided into “BIG Q” and “LITTLE Q” as described by Joseph M. Juran where BIG Q refers to the overall system of quality management for the total organization and LITTLE Q refers only to the processes for assuring quality at the production process or point of service delivery. Quality Promise An expectation for the performance outcome of a good or service that is delivered to a customer. Such an expectation may be either a deliberate promise (e.g., warranty or guarantee or specification), or it may be an implicit promise (e.g., ‘best’ or ‘world class’). Often this promise is supported by a “service level agreement” (SLA) that specifies the limits of performance for the promise. Quality System The organizational structure, responsibilities, procedures, processes and resources for managing product and process quality across an organization. Queue Time The amount of time that a product spends in line waiting for the next step in the operation to be performed Queuing Theory Principles and statistics related to the performance and productivity of service lines (e.g., waiting for service, service time, etc.). The performance of these functions is generally characterized using the Poisson distribution which is characterized by the mass of the data observations close to the “zero time” performance for waiting or service and a minority of incidents creating a “long tail” that shifts the average performance (mean) further toward the tail than the location of the median (50thpercentile of the data). R Charts Plot of the difference between the highest and lowest in a sample. Range control chart.
  19. 19. 18 RACI Responsible – Authority – Collaborate – Inform: labels for the set of relationships that define decision rights in a process. Radar Chart Also called a spider chart, polar chart or a Daetz diagram (after Douglas Daetz, the originator of this technique). The diagram has an origin from which linear vectors displaying measurements of process or product parameters emanate. This is a simple way to illustrate multivariate performance indicators at a point in time and is quite useful for graphing a system of performance factors that are influencing the output of a process (e.g., quality, cost, time, etc. all driving productivity). Random Selecting a sample so each item in the population has an equal chance of being selected; lack of predictability; without a systematic pattern. Random Cause A source of variation which is random and affects all of the data within a process; a change in the source (“trivial many” variables) will not produce a highly predictable change in the response (dependent variable), e.g., a correlation does not exist; any individual source of variation results in a small amount of variation in the response; cannot be economically eliminated from a process; an inherent natural source of variation. This variation is the sum of many unidentified factors that contribute to the variation routinely observed in a process, where each cause is of small relative importance (see COMMON CAUSE VARIATION). Random Effects Model Experimental treatments are a random sample from a larger population of treatments. Conclusions can be extended to the population. Interferences are not restricted to the experimental levels (see also FIXED EFFECTS MODEL and MIXED EFFECTS MODEL). Randomness A condition in which any individual event in a set of events has the same mathematical probability of occurrence as all other events within the specified set, i.e., individual events are not predictable even though they may collectively belong to definable distribution. Random Sample One or more samples randomly selected from a universe (population) where all members of the universe have an equal opportunity to be selected and there is no relationship between the choice for selecting one sample and the next sample (this means that there is independence between selections of the observations that are sampled). Random Variable A variable which can assume any value of a set of possible values. Random Variation Variations in data that result from causes that cannot be pinpointed or controlled (also called noise, common cause variation and natural variation) (see RANDOM CAUSE VARIATION). Range The difference between the highest and lowest values in a set of numbers which represent a rational subgroup Ranking Values assigned to items in a sample to determine their relative occurrence in a population. Ratio Numeric scale which has an absolute zero point and equal units of measure through, i.e., measurements of an output parameter, i.e., amps.
  20. 20. 19 Rational Sub-Group A logical grouping of objects or events th event-to-event variations, e.g., the objects or events are grouped to create homogenous groups free of assignable or special causes. By virtue of the minimum within group variability, any change in the central tendency or variance of the universe will be reflected in the “subgroup-to-subgroup” variability.displays only random Recognize The phase in the Six Sigma analysis process where the top level managers are engaged to determine the strategic issues which the business is facing as a way to prioritize selection of analysis projects. Regression Using one or more independent variables to predict changes in a dependent variable. An equation is formulated during a regression analysis to fit observations of activity (X’s) to an outcome measure or response. This prediction equality can be evaluated to determine the goodness of fit and statistical significance. Reject Region The region of values for which the alternate hypothesis is accepted. Reliability The delivery of sustained performance over time (e.g., software or hardware reliability). Also, the ability to repeat an experiment and obtain similar results. Repetition A strategy for improving experimental results by taking repeated samples during a single run of an experiment to determine short- term variation, measurement error, and noise. Replication A strategy to improve the quality of experimental results by repeating all of the experimental combinations that have been tested in an experiment; observations made under identical test conditions. This strategy observes an estimate of the long-term variation that occurs between the different set-up conditions of the experimental runs. Representative Sample A sample which accurately reflects the set of conditions that are the critical characteristics of a rational sub-group. Required Activity: A category of non-value added work which cannot be eliminated from a production process because the work output is required by a third party for legal, safety, environmental, or any other non- negotiable business reason that affects good governance of the organization. Requirements A minimum performance standard that has been established for the outcome desired by the customer of a product, service or process. Research Critical and exhaustive investigation or experimentation having with the objective to discover fact that could revise accepted conclusions about a theory or practice. Residual Error See EXPERIMENTAL ERROR. Residuals The amount of variation that remains unexplained once the sum of squares for the factors included in the regression model have been subtracted from the total sum of squares from the sampled data. Response . Outcome variable being studied (see DEPENDENT VARIABLE) Roadmap A time-sequenced program to introduce future new products that indicates what will be developed, when it is targeted for delivery as well as any sequential requirements when there is a dependency of one technology on prior technologies to achieve its successful application. Robust The conditions or state in which a response parameter exhibits hermeticity to external causes of a nonrandom nature (noise); i.e., impervious to perturbing influence. Able to accept variation in the inputs without causing variation in the outputs.
  21. 21. 20 Robust Design This experimental design technique was devised by Genichi Taguchi and is often called Taguchi Analysis. The method seeks to design a product so it functionality varies minimally despite the influence of disturbing factors; a design that is able to accept variation in the inputs without changing the output variability. Root Cause Analysis See CAUSAL SCREENING RTY Rolled Throughput Yield. The product of the first pass yield of the individual steps in a continuous flow process. RTY is the probability of producing the final production unit right the first time without rework, repair or retesting. Run Chart A form of line graph that plots individual data observations of a specific variable (quantified) as a function of a second variable (usually fixed time intervals). A dot is placed on the chart to indicate the performance level for the variable at that point in time. The successive dots are connected in accordance with their order of occurrence. Sample A selected sub-group of a population used to gain or predict information about the population; one or more observations drawn from a larger collection of observations or universe (population). Sampling The process of taking a small part or quantity (sample) that represents the larger collection for purpose of analysis. Scatter Diagram A graphical method used to study correlation, e.g., the relationship between two variables that indicates their strength of association. Seiri[Japanese] The first of the five S’s used to create a workplace that is suitable for the visual control of a lean production system – sort, structure, screen or sift – to put in order the work environment by separating necessary tools, parts and instructions from those that are not necessary and removing the unnecessary ones from the production environment. The activity simplifies the organization of the workplace. Seiton[Japanese] To set in order or systematize – to arrange neatly and identify parts and tools for ease of use. By organizing essential materials operators are able to find what is needed when it is needed because everything is in its correct location (see shadow board). Seiso[Japanese] To sanitize, sweep or shine – to conduct a cleanup campaign. A dirty environment is often the source of problems in reliability, safety or quality. Seiketsu[Japanese] To standardize the work process – to conduct the first three steps of the 5S process (seiri, seiton and seiso) as part of the daily routine in order to maintain the orderliness of the workplace. Standard work is documented using visual controls so that operators have clear communication of the daily routine and are able to follow the policy and procedures unambiguously. Sensei[Japanese] A teacher who has a profound mastery of a body of knowledge (lean production or Six Sigma). Setup Time The time for conversion or changeover of a production operation. It includes both external setup (work done off the line while production continues) and internal setup (work that requires stopping the line and loss of productivity to complete the changeover). Shared Values The mission, vision, common values, strategic direction and guiding principles that define a company’s purpose and also provide guidance for strategic choice and routine behavior of the organization’s people.
  22. 22. 21 Shadow Board A visual management method which indicates the proper placement of a tool by its painted outline in order to identify its storage location and assure fast sighting of any misplaced tools. Shewhart Cycle See P-D-C-A. Shitsuke[Japanese] To sustain or maintain self-discipline – to form a habit of using the four S’s of the 5S system to collectively assure an orderly, clean and efficient working environment Shojinka[Japanese] Continuously creating personnel capability improvement (e.g., flexible workforce) that possesses the required skills, training and knowledge to enhance the performance capability of a production cell. Sigma (σ) See STANDARD DEVIATION. Simulate The development of a model (either physical or compute-based) of a production environment in order to examine alternative ways to conduct the work and eliminate non-value-adding activities. SIPOC Map Supplier Inputs to the Process with Outputs to the Customer. This is a high- order map of a process that allows managers to talk about the activities performed but not sufficient to describe actual work activity. The map thoroughly describes input and output boundaries of the process but only provides a “block diagram” of activities in the process. Six Sigma A term devised at Motorola to express a process capability that produces only 0.0002 defects per million opportunities when the process is centered (Cp) and 3.4 defects per million opportunities when the process performance shifts by 1.5 sigma in process performance (Cpk) (see PROCESS CAPABILITY, Cp, Cpk). Six Sigma Analysis Process Projects conducted in a “Six Sigma” format follow a highly structured logical analysis process in order to accomplish their objective which is a specialized version of the PDCA cycle that uses the labels: Define-Measure-Analyze- Improve-Control (see PDCA). Skewed Distribution This phenomena occurs when the tail of a distribution has become elongated to the left or the right of its area of central tendency. The long tail in a work process can occur naturally in queuing processes (see QUEUEING THEORY). SMED Single Minute Exchange of Dies. A process developed by Toyota engineering consultant Shigeo Shingo to effect rapid changeover of production equipment in less than 10 minutes. The objective of SMED is to achieve such a rapid changeover of tools so that it is virtually instantaneous and does not interrupt the continuous flow of the production operations. SPC Statistical Process Control. A statistical methodology developed by Walter E. Shewhart that evaluates process performance data to determine if new observations come from the same population that produced the previous results. A control chart is plots the data history and the average performance of a process parameter of interest. The upper and lower control limits are calculated to compare new process data and also a series of probability-based pattern recognition tests are used to determine if performance of the process is operating in a state of statistical control (e.g., no unusual events that are outside the range of reasonable probability). When ‘out of control’ events are detected, a ‘special cause’ of variation is identified that must be investigated in order to determine what changed from the ‘common cause’ system of natural process variation. Investigation of a special cause of variation may lead to the root cause of a process performance problem.
  23. 23. 22 Stable Process A process that is free of assignable causes, e.g., the process is said to be operating in a state of statistical control. Stakeholder A person who has an interest in an organization: e.g., shareholder, customer, employee, or owner. Standard Deviation A statistical index of variability, dispersion, or spread of values within a statistical distribution, designated by “s” for a sample and “σ” for a population (see SIGMA). Standard Work: A precise description of the ‘one best way’ of working that specifies the cycle time, takt time, and minimum quantity of parts that should always be available for use during or between processes (buffer stock). All work is organized around the human activity to assure that human motion is performed in an efficient sequence without waste. Statistics Descriptive statistics involves the tabulation, depiction and description of a collection of data (data from a sample used to make informed judgments about the entire population). Inferential statistics is a formal body of techniques that is used to infer the properties of a large collection of data from the inspection of a sample from the collection Statistical Control A quantitative condition that describes a process that is free of assignable or special causes of variation, e.g., variation in the central tendency and variance. Such a condition is most often evidenced on a control chart, i.e., a control chart that displays an absence of nonrandom variation. Status Quo A condition in which the environment, process performance requirements, and customer expectations are in harmony. It does not mean that the system is performing satisfactorily from any one of these perspectives. Storyboard Techniques used to graphically summarize the methodology used and progress of a project. It is specifically designed to display information that defines and identifies the approach taken in a continuous improvement type of project. Stratification The creation of a grouped data set according to similar type characteristics or the separation of data into subsets that share similar characteristics (see RATIONAL SUB-GROUPS). Streamline Synonym for lean – a process for eliminating waste and cycle time from the production environment in order to assure the continuous flow of production. Stretch Goals Goals that are exceptionally difficult to reach and may not be obtainable unless an organization changes its way of working to achieve this performance. Quantitative stretch goals may be set by calculating the “ideal” performance of a process (e.g., the consistent achievement of the Cp process capability level) and determining the proportion of that value that should be accomplished within a fixed period of time by applying a designated implementation plan to achieve the required process improvement. Sub-Group See RATIONAL SUB-GROUP. Support Services Those business processes that deliver services primarily to internal customers (e.g., human resources, finance, quality, facilities management, security, information systems, etc.). Symptom An observable phenomenon that often accompanies a defect. Sometimes, but not always, the same word is used both as a defect description and as a symptom description (e.g., as when the symptom is also a cause). Defects tend to display multiple symptoms.
  24. 24. 23 System A group of interdependent processes and people that share in the performance of a common mission and work together to achieve it. Systematic Variation A pattern of variation in data which displays predictable tendencies such as shifts, trends, oscillation, or clustering. T Takt Time[German] The rate of customer demand which is calculated by dividing the time that is available for production by the quantity of products ordered by customers during that time. Takt is a German work which describes a beat as in a heartbeat or the beat of a metronome that defines the tempo of music. Tampering The process of adjusting a stable process to compensate for a single undesirable result; this results in decreased performance of the total system performance. Task Team A team that is focused on the performance of a particular task or activity and once completed is disbanded (also called a Tiger Team or Project Team). TCT Total Cycle Time. The total time from customer need identification to delivery of the product; the time from new product design concept to cost effective production; the time from identification of a new business opportunity to routine or stable operation. Team A group of people organized to work together in order to approach a common task or shared mission. Team Leader The individual who takes responsibility to move the team toward their common mission and focuses on the content and project management of the work to be accomplished. Team Member A participant on a team who contributes their unique skill, knowledge, or capability toward achieving a shared mission or accomplishing a common task. Teamwork The cooperative or collaborative effort by members of a team to achieve their common goal. Teiem[Japanese] An employee suggestion system used to solicit, analyze and implement ideas for continuous improvement from front-line workers. Test of Significance A procedure to determine whether a quantity subjected to random variation differs from a postulated value by an amount greater than that due to random variation alone. Theory A plausible or scientifically acceptable general principle offered to explain phenomena. Theory “O” Decisions Theory “X” type management decisions that are based on choices formed solely by opinions of senior managers, not based on data analysis (this refinement to Theory X was made by management consultant Gregory H. Watson). Theory “X” Decisions Decisions that are “dictated” by the management without the input, feedback or challenge by members of the organization (theory X and Theory Y were proposed by psychologist Douglas McGregor). Theory “Y” Decisions Decisions that are made with participation of the whole group where each has an opportunity to make their personal opinion heard (consensus management). Theory “Z” Decisions Decisions that blend the limits of Theory “X” and “Y” to balance the two limits of concern (Theory Z was proposed by management consultant William Ouchi).
  25. 25. 24 Throughput The rate at which a production system generates cash through sales or the conversion rate of inventory into shipped product. TQM Total Quality Management. A systematic approach for managing a business to achieve customer satisfaction and business results that involves all managers and employees and uses quantitative methods to analyze and continuously improve the performance of an organization’s processes (see QUALITY MANAGEMENT). Tracking The process of continuously monitoring a performance measure in order to determine how well a system continues to operate. Tree Diagram A graphical diagram that begins with a high-order concept, goal or activity and breaks it down into increasing levels of detail which bear a logical relationship to the top level. Trend Analysis The use of a run chart to study observed data for a process performance measure over a period of time in order to see trends or patterns in its real-time behavior. Trial Implementation A pilot test or demonstration of a potential problem solution in order to assess how well the solution resolves the conflict or issue and determine if it has any unintended consequences. TOC Theory of Constraints. Developed by management consultant Elihu Goldratt, this theory holds that resource flow is constrained at bottlenecks which should be managed to improve throughput (salable output) while decreasing both inventory (non-salable output) and operating expense. TPM Total Productive Maintenance. A process that smoothes the flow of material through the manufacturing process by continuously improving the production equipment efficiency and reliability through the use of reliability prediction, planned maintenance, and autonomous operator responsibility for equipment upkeep in a systematic process to reduce or eliminate equipment degradation or breakdown (equipment operation effectiveness, phased maintenance programs, machine operator training, and autonomous work groups). This system focuses on preventative behaviors and is tightly linked to the 5S process for housekeeping. Two-Sided Test A statistical hypothesis test where the values of the parameter that is evaluated are designated for both the upper and lower bound or two tails so that an assessment is based on equality or inequality of the null hypothesis (see HYPOTHESIS TEST). Type I Error See ALPHA RISK. Type II Error See BETA RISK. U Unnatural Pattern Any pattern in which a significant number of the observations do not group themselves randomly around a center line; when the pattern is unnatural, it means that an outside disturbance is present and affects the process. When an unnatural pattern exists in the residuals of an ANOVA or regression analysis, this is an indicator of the presence of a coherent signal (unknown X) that is not included in the analysis model. Upper Control Limit A horizontal line on a control chart which represents the upper limits of the inherent process capability (it is located approximately three standard deviations above the center line).
  26. 26. 25 Uptime The time that production equipment is available for operation – the total time it is available minus downtime (see operational availability and downtime). V VALIDITY The “correctness” of an experimental design to determine the effect of various factors Value A judgment of utility by a customer – either an item is worth what they paid for it or it is useful to get their job done at a cost that is tolerable. Judgments of the value of a product are subjective and typically are based on a comparison with alternative goods or services that could become a substitute. Value-Adding Activity Activities that transform inputs into customer usable output where the customer may be either an external consumer or an internal associate who is part of the flow sequence that delivers value to the ultimate consumer. Values The fundamental beliefs that define an organization’s way of working, behavior and decision making philosophy. The stated values may or may not match the actual values that are observed in the daily behavior of managers or workers. Value Stream All activities, both value-adding and non-value adding, that transform a raw material into a finished product that is ready for shipment to a customer. A value stream may be described from order to delivery (or installation), or it may be described from customer requirements through design to product launch. Variable A measureable factor that may take on different values (see EXPERIMENTAL FACTOR). Variables Data Quantitative information where measurement using a variable scale is possible; numerical measurements made at the interval or ratio level; e.g., ohms, voltage, diameter; subdivisions of the measurement scale are conceptually meaningful, e.g., 1.6478 volts Variation Any quantifiable difference between individual measurements, such differences can be classified as being due to common causes (random) or special causes (assignable). Variation Analysis Procedures, techniques, and methods used to isolate one type of variation from another (for example, separating product variation from test variation or different sources of variation (e.g., temporal, cyclical, and positional). VAT Value-Added Time. The increase in value that is contributed by the performance of a process transaction. The difference between the value of the input and the value of the output of a process where the value adds worth according to the external customer. Vision A definition or description of how we want to be viewed by our organization’s stakeholders at some point of time in the future. It defines what kind of company (or other business unit) we have chosen to become as well as how well we should perform; it can also have both descriptive and numeric objectives. Visual Controls: Any devices that allow workers to quickly manage the routine processes of production. These devices increase operator ownership for their work, clarify actions that are required, inform them of critical production information or indicate the standards of work performance. Visual control devices include: andon lights, painted floors, photo boards (e.g., for quality inspection requirements, recognition of employee achievements or specification of work standards), production status boards, shadow boxes, and kanban cards. VSM Value Stream Map. A graphical representation or process map of the value stream of a production line.
  27. 27. 26 X Waiting Time The time that equipment, people or material is idle and not involved in an activity of production. Wa[Japanese] Harmony within the workplace – a state achieved when all elements are in balance and synchronized. Waste Any activity that consumes resources and produces no value for the product or service that the ultimate customer desires (see muda). Work in Process (WIP) Production assemblies waiting to be processed or material that is in queue and idle. That part of the material inventory that is found between raw material and finished goods in the production process. Weighted Criteria Ranking A way to prioritize a list of issues, ideas or attributes using a system of weighted criteria to judge their relative value. World Class An organization that has achieved exceptional standards of business performance and is continuously improving its ability to meet customer demands. An organization that would be ranked in the top one percentile of peer organizations for performance. Workout A group decision process that is conducted in a time-constrained workshop. A workout requires a cross-functional team to meet and develop a defined position that is based on solid data analysis and recommends a course of action. The team of managers listens to the presentation, challenges the team on assumptions, data analysis, and logic, the then must make a firm decision: yes, no, or set a date for the decision to be made with requirements for additional data to drive a conclusion. X Xbar & R Charts A control chart that is a representation of process capability over time; displays variability in the process average and range across time. Y Yamazumi [Japanese] A cumulative measurement of key production indicators. The word has two roots “yama” or mountain and “zumi” or building up – so the word literally means “building-up mountains.” The measure is the total amount of time (in minutes or seconds) for all activity required to complete a finished product. Typically, this time falls into two categories: standard time tasks and muda. The timeline on a Value Stream Map is a logical equivalent of a Yamazumi chart. Yield Percentage of production output that is in conformance with the specification. This measure may be calculated in different ways: Total Yield (total output divided by total input); First Pass Yield (the percentage of product that goes through the operation without any rework); or Rolled Throughput Yield (the probability that a product will be produced right the first time). z Zero Defects A long-range value or concept. It implies the end-state of a never- ending improvement process and is practically seen as the achievement of six sigma quality performance. This philosophy was first proposed by management consultant Philip B. Crosby.
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