Diff between Story Points and Ideal Days

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Diff between Story Points and Ideal Days

Mon Dec 30, 2013 8:15 am

A few differences between Story Points and Ideal Days:

1. Story point is a unit less abstract number, while ideal days represent time it takes to develop story in ideal environment , ideal environment is .. you have no interruption, this is the only thing you have to work on and all you need is available

2. While we estimate in story points we estimate based on relative ranking like if A was 3 point then this story cannot be more than 3, while estimating in ideal days we think of how many ideal days in total will go in this story to make it as per definition of done.

3. Agreeing on relative rank or story point is relatively easy, like all will soon agree to that this is same sized story as story A, but agreeing on ideal days will take time since my ideal days may not be same as yours.

4. Story point does not give direct information of effort since co-relation between story point and effort comes gradually, but with ideal days management may get feel of effort one story will take, which makes ideal days easy to communicate to management

5. Story point estimate does not decay with time, mean you are ranking story so any new story which is like A you will rank 3 but ideal days decay with time, you may be taking 3 days for story A initially but if new work come of same size you may estimate it 2 since you know the system well.

In general majority of teams use story point since it represent the size , In case you end up using ideal days, use it as a measurement of size not effort.
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Re: Diff between Story Points and Ideal Days

Tue Jan 07, 2014 1:39 pm

Thanks Rachna for posting this.
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