| You
are here: Freetutes.com
> Systems
Analysis and Design
Software Estimation
Software measurements, just like any other measurement in the physical world,
can be categorized into Direct measures and Indirect measures. Direct measures
of the software process include measurement of cost and effort applied. Direct
measures of a product include Lines Of Code (LOC)
produced, execution speed, memory size, and defects reported over some set of
time. Indirect measures of the software process include measurement of resulting
features of the software. Indirect measures of the product include its functionality,
quality, complexity, efficiency, reliability, maintainability etc.
In the starting era of computers, software cost was a small proportion of the
cost for complete computer based system. An error in estimation of software didn't
have a major impact. But, Today software is the most expensive element in many
computer-based systems. Large cost estimation errors can make the difference between
profit and loss. Cost overruns can be disastrous for the developer.
Estimation is not an exact science. Too many variables - human, technical,
environmental, and political - can affect the ultimate cost of software and effort
applied to develop it.
In order to make a reliable cost and effort estimation there are lot of techniques
that provide estimates with acceptable mount of risk.
These methods can be categorized into Decomposition techniques and Empirical
Estimation models. According to Decomposition techniques the software project
is broken into major functions and software engineering activities (like testing,
coding etc.) and then the cost and effort estimation of each component can be
achieved in a stepwise manner.
Finally the consolidated estimate is the clubbed up entities resulting from
all the individual components. Two methods under this head are Lines
of Code (LOC) and Function Points (FP) Estimation.
Further Empirical Estimation models
are used to offer a valuable estimation approach, which is based on historical
data (experience).
<< Previous
Page | Contents
| Next Page >>
|
