Project Estimation -- how to? 2

[Kobojunkie]

I have been asked as a developer to come up with an estimate on a project. Problem is I am a newbie and have had a hard time in the past with estimating the time it would take to complete projects. This has cost us projects as well. I am being asked to come up with an estimate for a Mass mailer with an administrative web interface, database that contains as much data as possible about mail messages as well as reports for reporting about messages sent, and a mail sender service that runs on the server with access to the database and manages most all the processing needs of the system.

How do I go about coming up with an estimate for this please?

 

[Babynus]

Hi,

Estimate is the basis of success for a project manager.

Just start with what you know.
Define the screens, functions you will need and else.
Try for each to define a complexity : simple, complex, very complex, ...
Il you're a newbie in estimate, then you may be a developer.
So try to estimate the time it will take you to develop what you have listed, you will quickly find your own abacus (1 simple scren = 1 day, 1 compex screen = 5 days, ...).
Then think about all what you have to do before and after coding : specifications, tests, correcting bugs, ...
And just calculate the workload of these activites as ratios estimated from Dev workload.
For example :
- Specification = 40% of DEV
- Unit testing = 40% of DEV
- Writing integration test scenario = 20% of DEV
- Integration tests = 30% of DEV
- Correcting bug = 50% of tests.
- ...

Hope this helps.

Babynus
Moderator of

http://www.deltaprod.free.fr

(Yet Another Project Management Tool)

 

[jblack34]

You will find a number of articles on estimating here:

http://www.pmconnection.com/modules.php?name=Web_Links&l_op=search&query=estimat&orderby=hitsD

JBlack

http://www.pmconnection.com

 

[PDQBach]

A PM never comes up with the estimates for a project. Why? Because the PM isn't responsible for the deliverables of the project. The deliverables are the responsibility of the people who are making them. If follows, then, that the person best equipped to make the estimates is the person responsible for making the deliverable. These people, sometimes referred to as Subject Matter Experts (SMEs), prepare the estimates because they are aware of the deliverable and the environment in which it will be delivered (which resources are available to work on the deliverable, skill levels, vacation schedules, etc.) and they bring that information into play when preparing estimates.

So, in your case, you would only prepare estimates for the work you are responsible for (it appears you're wearing two hats here: PM and developer). For everything else, you need to get the estimates from others temporarily assigned to your project. This has the advantage of getting those people to "buy in" to the estimates they are providing.

 

[johnherman]

This just came out in today's newsletter:

http://blogs.techrepublic.com.com/tech-manager/?p=993&tag=nl.e053

-------------------------
The trouble with doing something right the first time is that nobody appreciates how difficult it was - Steven Wright

 

[mike30602]

Hi, friends this is mike iam a new member of this site. Recently i was visited one site (

http://www.propertymanagementbackoffice.com),

if we go through this we can solve project management and outsourcing property management problems.

 

[bfernandes]

if you are not sure how much time you need for every task, you can use the PERT Analysis. Basically you give 3 estimates for every task: optimistic, normal and pessimist.

Then take the estimates and calculate the task duration using the next formula:

DURATION = (OPTIMISTIC + 4 x NORMAL + PESSIMIST) \ 6

If normally your are an optimistic giving task duration, you can put more weight into the pessimist estimate, for example:

DURATION = (OPTIMISTIC + 3 x NORMAL + 2 x PESSIMIST) \ 6

This is the best way if you are not sure how much time takes every task. But remember, the best person to give a time estimate for a task, is the person who will complete it.