Type: Rules

## Gist

Calculate Effort from # of Function Points, for Enhancements

## Rules and Notes

R1: The Capers Jones Formula for Effort E of new Products (in person months):

(1)R2: Enhancements of products cannot be calculated with the same formula, as you need to take into account that you add complexity to an existing product.

R3: Formula for the needed EnhancementEffort EE for an Enhancement of y function points to a a base product of x function points:

(2)EE = E(x+y) - E(x)

*Note: Obviously you need to know y and x. The greater x is, the more significant is the difference between E and EE.*

## Costs, Savings

What does it take to implement those rules? What does it give?

## Side effects

Is there anything that happend or will happen as one implements the rules? This relates to both wanted and unwanted effects ('unwanted' does not imply 'negative').

## Related Pages

- 11 rules for prioritizing features
- lean product development
- how to state the credibility of estimations
- 10 Deadly Sins of Estimation (on Seer)
- Excellent Material on Professional Estimation (on Gilb website)

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