This document discusses operations research (OR), which is a quantitative approach to scientific decision making. OR uses interdisciplinary teams and modeling to determine the best use of resources. The OR process involves identifying the problem, collecting data, developing hypotheses and models, testing the hypotheses, and discussing alternatives. Common OR tools include linear programming, queuing theory, and PERT/CPM. OR has applications in many fields like finance, marketing, and manufacturing. However, OR models simplify reality and may not fully represent real-world systems.

1. Operations Research
By
Prof.P.D.Devan
Kumaraguru College of Technology
Coimbatore

2. Operations Research
• OR- A quantitative approach to Decision Making
in scientific manner.

3. Quantitative Approach
• Decision maker comes to a conclusion / solution
based on the quantified / numerical results among
the alternatives.
• Eg: Stock Market, Investment on gold,
Business

4. Qualitative Approach
• Most of the decision makers are not considering
this approach before arriving to a solution because
of its uncertainty.
• Eg: Weather, Sudden Govt Policies, Political Situation,
New technology

5. Quantitative Vs Qualitative

6. Definition of OR
• This new decision making field has been
characterized by the use of scientific knowledge
through interdisciplinary team effort for the
purpose of determining the best utilization of
resources.

7. Features of OR
• Interdisciplinary Approach
• Scientific Approach
• Holistic Approach
• Objective-oriented Approach

8. Phases of OR
Judgment Phase
• Identification of Problem
• Identification of appropriate objective & values of variable
• Deciding the scale of measurement
• Formulation of appropriate model to solve the problem

9. Cont…
Research Phase
• Observation & data collection
• Formulation of hypothesis and model
• Experimentation to test the hypothesis
• Analyze the information and verify the hypothesis
• Prediction of various results from hypothesis
• Discussion results/ alternatives.

10. Cont…
Action Phase/ Implementation
• Every individual must be aware of the decision.
• Objective, assumptions, constraints are to be
disseminated to all the stakeholders of an
organization.

11. OR Models
• An approximation or abstraction of reality which
considers only the essential variables and parameters in
the system along with their relationship.
• Models cannot be represented every aspects of reality.
Because the reality consists innumerable and changing
characteristics.

12. Cont…
• Model should be as simple as possible.
• Oversimplifying leads to poor decision.
• Model can be enriched through
 adding variables,
 changing constants in to variables,
 relaxing linearity and assumptions.

14. Qualities of the Model
Validity- How the model will represent the critical aspects
of the problem.
Usability- Whether the model can be used for specific
purpose.
Value- Worth to solve ?
Cost and Time

16. OR Methodology

17. OR Tools
• Linear Programming
• Sequencing
• Queuing Theory
• Transportation Problems
• Assignment Problems
• Games Theory
• Replacement Problems
• PERT & CPM

18. Applications of OR
• Finance and Accounting
• Marketing
• Project scheduling
• Government
• Manufacturing

19. Limitations of OR
• Problems are often simplified / assumptions are
incorporated
• Model may not represent the actual behavior of
the system
• Lack of decision makers awareness
• Many real world problems can not have OR
solution