Use Case Based Project Estimation (Modeling Tool EA)

Authors	Zhang Kexin, Zu Tao
Date	October 2023

2023-10-20

1、 Introduction to project estimation based on use cases

Project estimation is one of the most difficult tasks in software development, and project estimation of a software project is a prediction of the workload, time, and cost spent on the entire software development process, such as requirements analysis, design, coding, testing, and integration delivery.

Project estimation is the basis for making a reasonable project plan, and project management is inseparable from the following major issues: scope of work, time, cost, quality, resources and risk. Faced with these problems, we need to make a reasonable project estimate.

We can use use cases to describe the functional requirements of the system, and the main object of the project estimate is the functional requirements. Project managers can estimate the effort, time, and cost of a project based on use cases.

2、Use case estimation function in the modeling tool EA

In the modeling tool EA, users can build use case models, which are the basis for use case estimation. The ability to estimate based on a use case model is available in the EA. The Use Case Estimation feature in EA can estimate the complexity of the estimated project by estimating the effort, time, cost, and more required to implement the project.

The following is a report of the estimated effort of the use case project based on the chat room model, which can reflect the projected effort of the project, the estimated cost, the degree of technical complexity factors, and the environmental complexity factors.

2.1 How to turn on the use case estimation function in the modeling tool EA

Open the method of use case estimation in EA: Settings - Reference Data - Model Type --- Estimation Factor. Here's how it looks:

2.2 What are the metrics for use case estimation?

In EA, there are three types of use case estimation indicators:

• Technical complexity metrics

• Environment complexity indicator

• Labor hours metrics

Let's take a look at each of the indicators. The interface view for defining the estimated metrics for a use case is as follows:

2.2.1 Technical Complexity Indicators

The abbreviation for Technical Complexity Metric is TCF, and the sample model in the EA contains a default set of Technical Complexity Metrics (TCFs) that we can add or modify using the Estimation Factor dialog. This set of metrics should include all metrics that may affect the technical complexity of the project environment.

Here are the technical complexity indicators for instructions:

Item	illustrate
Factor Number	Factor number
Description	Illustrative information
Weight	The importance of technical complexity
Assigned Value	Assignment value, which indicates the degree to which the factor affects the project
Unadjusted TCF	The Unadjusted TCF Value is combined with the technical complexity factor to skew the overall complexity up or down depending on the level of technical complexity and the corresponding level of technical support.

2.2.2 Environment complexity indicator

The abbreviation for Environment Complexity Indicator is ECF, and the sample model in the EA contains a default set of Environment Complexity Indicators (ECFs) that we can add or modify using the Estimator dialog. This set of metrics should include all metrics that may affect the general design and development environment, including team experience and knowledge, team size, expertise, and other non-functional metrics.

Here are the descriptions of the Environment Complexity Indicator:

Item	illustrate
Factor Number	Factor number
Description	Illustrative information
Weight	The weight of the complexity of the environment
Assigned Value	Assignment value, which indicates the degree to which the factor affects the project
Unadjusted ECF	The Unadjusted ECF Value, combined with the technical complexity metric, fine-tunes the overall complexity up or down based on the level of technical complexity and the corresponding level of environmental support.

2.2.3 Hourly Rate Metrics

Setting an hourly rate is the hardest metric in project estimation, and hourly rates can range from 10 to 30 hours per project use case point.

The best way to estimate an hourly rate is to complete a project estimate in EA by appropriately adjusting the values of the project duration and hourly rate by analyzing previously completed projects.

The following are the relevant metrics for the default hourly rate description:

Item	illustrate
Set the project defaults for duration and hourly rate for the Use Case effort estimati on	Set the project default duration and hourly rate for the use case effort estimate
Duration	Project duration
Hourly Rate	Project hourly rate

2.3 Description of the use case-based project sizing feature in EA

Project sizing is also available in EA, and the method of entering project sizing is as follows: Select Build - Project Management - QA - QA Report - Use Case Estimation, the view is as follows:

Here's how it works:

Project	Illustrate
Root Package	The root package, the top-level package of the estimated content, all use cases under this package may be included in the report.
Reload	Re-run the load from the selected package, which is typically used after changing the filter criteria.
Phase like	Stage, which is used to select the use cases that are in that stage.
Keyword like	Keywords, which are used to select use cases that have that keyword.
Bookmarked	Bookmarked, including all use cases, or just marked or untagged use cases:
Use Cases	Displays the total number of use cases in the estimate. For example, the total number of use cases in the chat room model is 28.
Include Actors	For included participants, selecting this checkbox indicates that participants are included in the estimate.
Technical Complexity Factor	Technical Complexity Factor, a parameter that describes the technical complexity of a project, Unadjusted TCF Value from the Technical Complexity Factor tab of the Estimation Factors dialog box, which constitutes the use case point method formula. These fields need to be modified carefully, and the final project estimate is proportional to the TCF.
Environment Complexity Factor-	Environmental complexity factor, a parameter that describes the level of non-functional environmental complexity of a programmer's experience, knowledge, or expertise. The Unadjusted ECF Value comes from the Environment Complexity Factors tab of the Estimators dialog box, and it forms the use case point method formula. The final project estimate is also proportional to the ECF.
Unadjusted Use Case Points (UUCP)	Unadjusted Use Case Points (UUCP)
Ave Hours per Use Case	Average hours per use case, the average number of hours allocated to easy, moderate, and hard use cases. These numbers cannot be changed.
Total Estimate	Total estimates, see the details of the final estimates.
Default Rate	Default Ratio, which sets the project duration and hourly rate for the use case effort estimate Duration- Duration: The duration of the project Hourly Rate: The hourly rate of the project
Re-Calculate	Recalculate, and the estimate needs to be rerun after changing the hours or use case points.
Report	Reports, which generate reports in rich text format based on current estimates.
View Report	View the generated report.

3 、Example of project estimation based on use case

Below we illustrate how to use use use cases for project estimation through the Chat Room sample project. The following is a report of the estimated effort for the use case project of the Chat Room Model, which can show the estimated effort of the project, the estimated cost, the degree of technical complexity factor, and the degree of environmental complexity factor. Here's how it looks:

In the estimation, the ratio value of the corresponding indicator can be adjusted according to the actual situation of the project to make the estimation more accurate.

Here's how each of the two metrics can be adjusted:

• Estimation metrics in technical complexity and environmental complexity

• The value of the project duration and hourly rate.

3.1Adjust the impact of technical complexity and environmental complexity factors on project estimates

The following view shows the estimated effort of the project calculated before adjusting the technical complexity and environmental complexity estimation factor values.

The following view shows the estimated effort of the project calculated after adjusting the technical complexity and environmental complexity estimation factor values.

3.2 Adjust the impact of project duration and hourly rates on project estimates

Let's adjust the values of Project Duration and Hourly Rate from 14 to 15 and 28 to 30 for the Hourly Rate, and then click "Recalculate" to get a different estimate for the project. Here's how it looks: