Technical writing/Cost and schedule estimating

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All projects cost time and money. It is important to accurately estimate how much a project will cost.

Most projects are late and more expensive than planned.

Cost and Schedule Estimates for Documentation
According to a study on Estimating Software Costs, documentation accounts for 10% of the total cost of a project.

Automated Estimating Systems
The use of automated estimating tools can greatly improve the accuracy of cost and schedule estimates, when compared to their human equivalents.

In most projects with a Function Point score of more than 10,000 the costs of documentation and defect removal are greater than that of creating the project itself.

Function Point
Devised in the 1970s, function points are used to assess the amount of functionality available to an end user from an information system.

There are 5 types of function points:


 * Outputs
 * Inquiries
 * Inputs
 * Files
 * Interfaces

Function Point Analysis is the amount of functionality which is relevant to and recognized by the user. As a rough estimate, there are 1000 Function Points per 125,000 lines of code.

Common Functions of Automated Estimating Tools

 * Estimate time and cost at phase, activity and task level
 * Make adjustments for work periods, holidays and overtime
 * Consider local salaries and workload
 * Adjust for project type
 * Support Function Point, LOC metrics or both
 * Handle conversions between Function Point and LOC
 * Support new projects as well as maintenance and upgrade projects

Advanced Functions

 * Estimates quality and reliability
 * Analyses risk and value
 * Estimates return on investment
 * Shares data with other project management tools
 * Assesses historical data according to measurement models
 * Supports process assessments
 * Provides statistical analysis for multiple projects
 * Currency conversion for international projects

Variable Factors
As all projects are different, there are factors which change according to the project. A good automated estimating system will take these variables into account.


 * Staff experience
 * Client expectations
 * Product type being developed
 * Size of deliverables
 * Project size
 * Design method used
 * Requirements method used
 * Available re-usable materials
 * Testing methods used
 * Overtime status - paid/unpaid

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