Applications are software programs designed to perform functions for users. They use operating system services and other supporting programs to perform a designated function.
Before developing an application, it would be nice to have an estimate of its size in terms of effort and/or costs.
Applications can be big and complex or small and simple.
An application that needs to interface and interact with users can be characterized by a certain number of elements such as wire-frames (or user interfaces), use cases, business rules, data tables, reports, and correspondences. The size of an application can be determined by the number of these elements. The table below describes a hypothetical example.
Application
|
Estimated Number of Elements
| |||||
Wire-frames
|
Use Cases
|
Business Rules
|
Data Tables
|
Reports
|
Correspondences
| |
10
| 50 | 90 | 100 | 10 | 15 | |
Estimated effort to develop one element of simple complexity level in man-days
|
3
|
5
|
3
|
3
|
2
|
2
|
Development Effort (man-days)
|
30
|
250
|
270
|
300
|
20
|
30
|
Estimated effort to capture one element during the analysis phase of simple complexity level in man-days
|
3
|
3
|
3
|
3
|
1
|
1
|
Analysis Effort (man-days)
|
30
|
150
|
270
|
300
|
10
|
15
|
Total Effort (man-days)
|
60
|
400
|
540
|
600
|
30
|
45
|
Legend of elements:
-Wire-frames are user interfaces and it’s the way the user communicates with the application.
-Use Cases describe how a user interacts with the application in a procedural way.
-Business Rules govern the flow of procedures and data.
-Data Tables are the data required for the application to perform its function.
-Reports are printable information.
-Correspondences can be notes, messages, and emails.
N.B.- The numbers in the table above do not refer to any particular industry standard, they are all hypothetical numbers just for calculation and illustration purposes.
-Wire-frames are user interfaces and it’s the way the user communicates with the application.
-Use Cases describe how a user interacts with the application in a procedural way.
-Business Rules govern the flow of procedures and data.
-Data Tables are the data required for the application to perform its function.
-Reports are printable information.
-Correspondences can be notes, messages, and emails.
N.B.- The numbers in the table above do not refer to any particular industry standard, they are all hypothetical numbers just for calculation and illustration purposes.
By introducing hypothetical unit rates per day it’s possible to calculate the relative and total costs.
-Development unit rate per day = $300
-Development unit rate per day = $300
-Analysis unit rate per day = $500
Costs
| ||
Total Effort Development in man-days
|
900
| |
Developers rate per day in $
|
300
| |
Developers Cost in $
|
270000
| |
Total Effort Analysis in man-days
|
775
| |
Analyst rate per day in $
|
500
| |
Analysts Cost in $
|
387500
| |
Total Cost in $
|
657500
| |
All data in this example is hypothetical. For better accuracy, it’s possible to add more variables and factors to this approach.