Estimating

"How long" - Ace

If software development were to be described as an 'art' and not a 'science' then estimating would be 'the black art'. In fact, even if systems development is a science the estimating could still be described as 'the black art!'

How Do You Do It?

The best demonstration of how to estimate I have ever seen was where the Systems Development Manager put on one of those huge great foam hands with a pointing finger. He then pointed at one of his staff and yelled, 'Hey, you, how long will it take to do this, its up to you, and you better get it right because I'm gonna check up on you!' Now this may not seem very scientific but lets understand some of the principles behind it;

1. Have the estimating done by someone who knows the language, business area, system involved, etc.

2. Make it clear that those giving them will have to stand by the estimates they give.

3. Do not interfere with the estimate once given without the 'giver's' agreement.

4. Create metrics to track the effectiveness of estimates that have been given.

It can be surprising the thought and experience that can lay behind a seemingly simple statement. By the way, the individual with the foam hand produced very accurate estimates and could tell you by how much people were out and how accuracy varied with size.