Date: Tue, 21 Dec 2004 15:50:37 -0500
Reply-To: Dianne Rhodes <RHODESD1@WESTAT.COM>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: Dianne Rhodes <RHODESD1@WESTAT.COM>
Subject: Re: Somewhat OT statistical programming question
> -----Original Message----- from Peter Flom:
> For those of you who have written statistical programs (in
> SAS, SAS IML, or otherwise):
> How do you estimate the time it will take you to do a project?
> e.g., if the project is to create code to run some model that
> doesn't exist in SAS STAT, how do you know if this will take
> you an hour, a day, a week, or a year?
I always liked the SWAG method - guess how long it will take you on your
best day, multiply by 2 and raise it a unit. So if you think it might take
4 hours, that becomes 8 days.
The other more traditional way I have done it is to break it up into
segments of work and use some kind of workflow tool, like MSProject, to
enter dependencies. This way you can see the critical path to completion,
and know when you are going to get behind. For example on one project I
scoped out, continuing on to the next phase was dependent on the client's
acceptance of the work. We gave them 3 days to turn it around; if they took
longer we could go to them and say they were impacting on the schedule.
If you do a google search on critical path you will numerous sites to
describe Gantt charts, PERT charts, and so forth.
Here are some good examples:
It's really more of an art than a science and I had gotten quite good at it.
At one point that was all I was doing and the projects themselves never got
the go-ahead. But I knew how long it would take!
Dianne Louise Rhodes
Sr. Systems Analyst