Software Cost Estimation By Deepika Chaudhary

In project planning process a project is split into a number of activities which are performed in parallel or sequence. One of the major issue is to associate estimates of effort and time with the identified project activities. Project managers must estimate the answer to the following questions

How much effort is required to complete an activity. How much calendar time is needed to complete an activity. What is the total cost of an activity.

Parameters There are three parameters involved in computing the total cost of a software development project. H/w and S/w Cost Travel and training cost Effort Cost

Decomposition Techniques Because cost and effort estimate is to complex so we decompose the problem into smaller manageable problems. There are two different approaches for software decomposition Software Sizing Problem based estimation Process based estimation

Software Sizing The accuracy of a software project estimate is predicted on a number of things The degree to which the planner has properly estimated the size of a product to be built. The ability to translate the size into human effort calendar time etc.

The degree to which the project plan reflects the abilities of a software team Sizing represents the project planner first major challenge. There are different approaches to a sizing problem

LOC Function Point Fuzzy Logic Change Sizing Fuzzy logic-Uses the approximate reasoning technique that are the corner stone of fuzzy logic.

Change Sizing – is used when a project encompasses the use of existing software that must be modified in some way a part of a project.

Problem Based Estimation In problem based estimation also we talk of two techniques. An estimation variable to size each element of software A baseline metric collected from past projects and used in conjunction with estimation variables to develop cost and effort projections.

Process Based Estimation The most common technique for estimating a project is to decompose project into smaller manageable chunks and the effort required to accomplish each task is estimated. Once the problem functions and process activities are melded the planner estimates the effort ( Person – month) required to accomplish each software process activity for each software function.