Back to Estimating Activity Durations

Analogous Estimating

5 minutes 5 Questions

Analogous estimating is a technique used in project management to estimate the duration or cost of an activity or project based on historical data from similar activities or projects. It is often utilized in the early stages of project planning when limited detailed information is available. By referencing previous projects that are comparable in size, complexity, scope, and other relevant factors, project managers can derive estimates for the current project's activities. This method relies heavily on expert judgment and the experience of those involved in the estimation process. The accuracy of analogous estimates depends on the degree of similarity between the past and current projects and the expertise of the estimators in identifying and adjusting for differences. Analogous estimating is considered a top-down approach, as it starts with the overall characteristics of past projects to estimate the current one. One of the advantages of analogous estimating is its relative speed and simplicity. It requires less time and resource investment compared to more detailed estimation techniques, making it suitable for initial planning phases or when quick approximations are necessary. However, it may be less accurate than other methods because it doesn't account for the detailed nuances of the specific activities being estimated. To enhance the accuracy of analogous estimates, project managers should carefully select historical data from projects that are closely aligned with the current project in key aspects. Adjustments may be necessary to account for differences in technology, team experience, market conditions, or other variables that could impact activity durations. Analogous estimating can also be combined with other estimation techniques to improve reliability. In summary, analogous estimating is a practical technique for estimating activity durations by leveraging historical data from similar projects. Its effectiveness depends on the quality of the data used and the judgment applied in adjusting for differences. It serves as a useful tool for project managers when detailed information is lacking or when quick estimates are needed, but it should be used with caution due to its potential for lower accuracy.

Analogous Estimating in Project Management

What is Analogous Estimating?

Analogous estimating is a technique used in project management to estimate the duration, cost, or size of a project by comparing it to similar past projects. It's considered a top-down estimation technique that uses historical data from previous similar projects as the basis for estimating the current project.

Why is Analogous Estimating Important?

Analogous estimating is important because it:

- Provides quick estimates when detailed information is limited
- Requires minimal time and resources to develop
- Works well in early project stages when scope details are still emerging
- Leverages organizational knowledge and experience
- Helps validate estimates created using other methods
- Creates a starting point that can be refined as more information becomes available

How Analogous Estimating Works

1. Identify similar past projects: Find completed projects with similarities to your current project

2. Determine relevant parameters: Choose which characteristics are most important for comparison (size, complexity, team skills, etc.)

3. Assess the degree of similarity: Evaluate how closely the past projects match your current project

4. Apply expert judgment: Use subject matter expertise to adjust the historical data based on differences

5. Create the estimate: Use the historical data with appropriate scaling factors to produce your estimate

Key Considerations:

- Accuracy level: Generally less accurate than other methods (typical accuracy range: -25% to +75%)
- Scaling factors: May need to adjust for size, complexity, or technology differences
- Expert judgment: Relies heavily on expertise to identify relevant past projects
- Documentation: Document assumptions and reasoning behind your analogies

Exam Tips: Answering Questions on Analogous Estimating

1. Recognize when to use it:
- Early project phases
- Limited detailed information available
- Need for quick estimates
- Previous similar projects exist

2. Know its strengths:
- Speed and low cost
- Simplicity
- Leverages historical knowledge
- Useful for high-level planning

3. Understand its limitations:
- Less accurate than parametric or bottom-up methods
- Highly dependent on truly comparable projects
- Subject to personal bias
- May overlook project-specific elements

4. Remember it's considered a form of expert judgment:
- Based on experience and historical data
- Requires subject matter expertise

5. Distinguish from other estimation techniques:
- Parametric estimating: Uses statistical relationships and parameters
- Three-point estimating: Uses optimistic, most likely, and pessimistic scenarios
- Bottom-up estimating: Estimates each work package in detail and sums them up

6. Understand its typical accuracy range:
- Less precise than detailed methods
- PMI recognizes it as having broader variance than other techniques

7. Be aware of when analogous estimates get refined:
- As more project details become available
- At key decision points in the project
- When moving from high-level to detailed planning

In exam scenarios, look for situations where rapid estimates are needed with limited information, or where the question mentions comparing to similar past projects. This often indicates analogous estimating is the appropriate technique.

Test mode:
Start practice test
PMI-SP - Estimating Activity Durations Example Questions

Test your knowledge of Amazon Simple Storage Service (S3)

Question 1

When using Analogous Estimating, what is the most essential characteristic of the historical data being used?

Correct Answer: The level of similarity between the projects' key parameters

The most essential characteristic of historical data when using Analogous Estimating is the level of similarity between the projects' key parameters. This is fundamental because: Analogous estimating relies on comparing and using data from past similar projects to estimate current project parameters. The more similar the historical project is to the current project, the more accurate the estimate will be. The key parameters that need to be similar might include scope, complexity, size, duration, budget, industry, technology, and other relevant factors. The other options are less critical for analogous estimating: Extensive documentation, while helpful, is not the most crucial factor if the projects aren't similar enough. Statistical validity across multiple years is more relevant for parametric estimating than analogous estimating. Comprehensive cost breakdowns are useful but not as essential as having similar project characteristics for analogous estimating.

Question 2

When implementing Analogous Estimating for a new multi-story office project, what factor contributes most to a reliable preliminary estimation?

Correct Answer: Using data from recent projects with similar scale and complexity

In Analogous Estimating, the most reliable preliminary estimates come from using data from recent projects with similar scale and complexity. This approach provides the most relevant and comparable data points for accurate estimation. The correct option focuses on two critical aspects: recency and similarity. Recent projects reflect current market conditions, labor rates, and construction methods. Similar scale and complexity ensure the comparison is meaningful and applicable. The other options are less effective because: - Looking at all historical data regardless of type dilutes the accuracy by including irrelevant projects - Standard industry benchmarks are too generic and may not capture specific project characteristics - Creating an average baseline from multiple past projects can skew results by including non-comparable data Analogous estimation works best when using carefully selected comparable projects rather than broad averages or generic benchmarks. The key is finding the right balance between having enough reference data while maintaining relevance and similarity to the current project.

Question 3

As a project manager using Analogous Estimating, what primary characteristic of data comparison contributes most to producing reliable results?

Correct Answer: The high degree of similarity between project components and parameters

In Analogous Estimating, the most crucial factor for reliable results is having highly similar projects to compare against. This similarity should extend to key project components, parameters, and overall scope. The correct answer emphasizes this fundamental requirement of analogous estimating - the high degree of similarity between projects being compared. This similarity ensures that the estimates derived from historical data are relevant and applicable to the current project. The other options are less critical for analogous estimating: Extensive documentation, while helpful, does not compensate for lack of similarity between projects. Precise mathematical adjustments are more associated with parametric estimating than analogous estimating. While team expertise is valuable, it is secondary to having comparable project characteristics. Even expert teams cannot make accurate analogous estimates if the reference projects are fundamentally different from the current project.

Go Premium

PMI Scheduling Professional Preparation Package (2025)

  • 3429 Superior-grade PMI Scheduling Professional practice questions.
  • Accelerated Mastery: Deep dive into critical topics to fast-track your mastery.
  • Unlock Effortless PMI-SP preparation: 5 full exams.
  • 100% Satisfaction Guaranteed: Full refund with no questions if unsatisfied.
  • Bonus: If you upgrade now you get upgraded access to all courses
  • Risk-Free Decision: Start with a 7-day free trial - get premium features at no cost!
More Analogous Estimating questions
59 questions (total)
Start 59 question test