Effort estimation is a process in which project managers evaluate how much time and money they need for completing a project. This technique is common in software development, where technology professionals define the resources and schedule for developing a new application or releasing an update. These forecasts help create accurate estimates that often require approval before work on a project begins. Effort estimation is a common tool as part of the Agile methodology, which is a framework that divides a project into smaller phases. In this framework, you can estimate the effort for several components of development, including: Epics: Epics are large projects that several teams manage throughout development. These usually contain several smaller releases and tasks. Features: A feature is a piece of functionality or design that addresses a user's need. A feature often includes specific acceptance criteria that detail how that part of the product works. Sprints: A sprint is a short period containing a fraction of work. Often, a few team members complete development tasks in sprints that build toward epics and releases. Releases: Releases are software packages development teams can deploy. These often contain several epics and features that teams deploy in iterations. Development teams might estimate the effort for each of these components of the Agile framework or select components depending on the needs of the project.

1. Effort Estimation
Meaning, Problems with Estimation, Basis
Estimation Techniques, Albrecht Function Point
Analysis, Functions Mark II, COCOMO Model
Unit-5

2. Effort Estimation
Effort estimation is a critical process in project management
and software development, involving the prediction of the
amount of effort (usually measured in person-hours or
person-days) required to complete a project. Accurate effort
estimation helps in planning, budgeting, scheduling, and
resource allocation.

3. Meaning of Effort Estimation
Effort estimation aims to forecast the resources needed to
complete a project within a defined scope. It involves
assessing the complexity and size of the project to determine
the necessary time and effort.

4. Problems with Estimation
• Uncertainty: Incomplete or unclear requirements can lead to
inaccurate estimates.
• Complexity: The complexity of software projects can be difficult to
gauge.
• Experience: Lack of historical data or experience can affect the
accuracy of estimates.
• Bias: Estimators might be overly optimistic or pessimistic.
• Dynamic Scope: Changes in project scope can invalidate initial
estimates.
• Stakeholder Pressure: Pressure from stakeholders to reduce time or
cost can lead to unrealistic estimates.

5. Basis of Estimation
• Project Size: Measured in terms of lines of code (LOC), function
points, etc.
• Complexity: Technical difficulty and complexity of the project.
• Resources: Availability and capability of the project team.
• Historical Data: Data from similar past projects.
• Expert Judgment: Insights from experienced practitioners.

6. Estimation Techniques
• Expert Judgment: Relies on the experience and intuition of experts.
• Analogous Estimation: Uses data from similar past projects as a
reference.
• Parametric Estimation: Uses mathematical models to predict effort
based on project parameters.
• Delphi Technique: Uses a panel of experts who provide estimates
anonymously, with feedback rounds to converge on a consensus.
• Three-Point Estimation: Considers optimistic, pessimistic, and most
likely scenarios to calculate a weighted average.
• Use Case Points: Estimates effort based on the complexity and
number of use cases.
• Wideband Delphi: An extended version of the Delphi technique with
more detailed rounds of estimation.

7. Albrecht Function Point Analysis
Function Point Analysis (FPA), developed by Allan Albrecht at IBM, is a
method for measuring the size of software by quantifying its
functionality based on user requirements. It involves:
• Identifying Functions: Categorizing functions into external inputs,
external outputs, external inquiries, internal logical files, and external
interface files.
• Assigning Weights: Assigning complexity weights (simple, average,
complex) to each function.
• Calculating Function Points: Summing the weighted counts to get the
total function points.
• Adjusting for Complexity: Adjusting the count based on technical
complexity factors.

8. Functions Mark II
Functions Mark II is an enhancement of the original function point
analysis. Developed by Charles Symons, it refines the estimation by
focusing on:
• Logical Transactions: Grouping user transactions into logical
categories.
• Data Element Types: Measuring the data elements within each
transaction.
• Entity Types: Considering the types of entities or objects manipulated
by the transactions.

9. COCOMO Model
The Constructive Cost Model (COCOMO) is a parametric model
developed by Barry Boehm for estimating the effort, cost, and schedule
of software projects. There are several versions, including COCOMO II.
Key elements include:
• Basic COCOMO: Provides estimates based on the size of the software
project measured in thousands of lines of code (KLOC).
• Intermediate COCOMO: Considers additional factors such as product
complexity, personnel capability, and project environment.
• Detailed COCOMO: Breaks down the software project into individual
components, applying effort multipliers for different factors at the
component level.

10. COCOMO uses the formula

11. Conclusion
Effort estimation is a foundational aspect of project management that
requires careful consideration of various techniques and models to
enhance accuracy and reliability.
Approaches like Function Point Analysis, Functions Mark II, and the
COCOMO model offer structured methods to predict the necessary
effort, contributing to more successful project outcomes.

12. Questions
• What is effort estimation, and why is it crucial in project management?
• What are the common challenges faced in effort estimation, and how can they
impact project outcomes?
• Explain the Expert Judgment technique for effort estimation. What are its
advantages and disadvantages?
• What is Parametric Estimation, and how does it differ from other estimation
techniques? Provide an example of a parametric model used in software
development.
• What is Function Point Analysis (FPA), and what are the steps involved in
calculating function points?
• Describe how complexity weights are assigned in Function Point Analysis and how
they influence the final function point count.

13. Questions
• What is Functions Mark II, and how does it enhance the original Function Point
Analysis method? Compare the two approaches.
• What is the COCOMO model, and what are the primary differences between
Basic COCOMO, Intermediate COCOMO, and Detailed COCOMO?
• Explain the formula used in the COCOMO model for effort estimation, including
the significance of constants and effort multipliers.
• Given a software project with 50 KLOC (thousand lines of code), use the Basic
COCOMO model to estimate the effort required, assuming typical values for
constants and effort multipliers. Describe each step of your calculation.

14. Thanks