W3 – FUNCTION POINT ESTIMATION

Hello!

Today we want to show you our function point estimation.

First of all we will give you a little explanation about function points.

Function points are used for estimating the time that will be spent on a certain Use Case. They are calculated in reference on External Inputs, Outputs, Inquiries as well as Internal and External Logical Files from the User’s view, thereby they do not depend on the used technology.
To estimate how long it will take to implement a Use Case, function points of UC that have been already implemented are put in relation to the time we spent on it.
We used the calculation for our function points from „TINY TOOL„.

Now to the actual work we done.

The following table shows our completed Use Cases with the time we needed to implement. You can also see the at the beginning explained references we calculated the function points on.

The acronyms DET, RET and FTR mean Data Element Type, Record Element Type and File Type Reference. Through these we identified the complexity which can be low, average or complex.
Here you can find the whole document which also includes the data for the new Use Cases. In this document you also see the estimation for the new Use Cases these get explained later in this blog entry.

For the calculation of function points with TINY TOOL you need some extra information about the whole application.

In this screenshot you can see what we choose for our project.

We calculated the function points for all our Use Cases. For example in the next picture you can see the table for the Use Case „Relay Message“.

Domain Characteristic Table

This Use Case has 81,9 function points. Here you can see the whole document.

 

With the calculated function points we generated a diagram which shows the interact of the function points and the person hours.

FP calculation and time estimation diagram

We used this graph to estimate the time for our remaining Use Cases. In the graph you can see these as orange dots. You can only see four dots, because two Use Cases („encrypted chat“ and „visualize lobby“) have the same amount of function points. Below you can see our time estimation for our new use cases.

 

I hope you liked it and if you want give us some feedback.

Greetings,

NeCo