Project Estimation can be done using following ways:
Lines of code
Functional Point (FP) Analysis
Lines of Code
The best known technique using LOC (Lines of Code) is the COCOMO (Constructive Cost Model), developed by Boehm. This model uses not only the LOC, but also other factors such as product attributes, hardware limitations, personnel, and development environment. These different factors lead to one or more "adjustment" factors which adjust the direct evaluation of the effort needed. In COCOMO's case, there are fourteen such factors derived by Boehm. This model shows a linear relation between the LOC and the cost.
Another model for this category (LOC) is the Putnam Estimation Model. This model includes more variables, and is non-linear in nature. The estimation is affected not only by the LOC, but also by the software development environment and desired development time.
Functional Point (FP) Analysis
Estimating using Functional Metrics
Provide a top down estimating approach
Based on the estimate of customer requirements & constraints
Consider the technical environment , project characteristics and past performance
Communicate accurate estimates which can be revised if requirements changes through
