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yetiheheyesterday at 8:25 PM3 repliesview on HN

I think software is one of those VERY rare things, where inaccurate estimates can actually be inaccurate by "orders of magnitude". After 20 years in the field, I still managed to use 2 months of time on a task that I estimated as 10 days.


Replies

camel_gopheryesterday at 8:48 PM

A rule that has suited me well is to take an estimate, double it, and increase by an order of magnitude for inexperienced developers. So a task the say would take two weeks ends up being 4 months. For experienced developers, halve the estimate and increase by an order of magnitude. So your 10 days estimate would be 5 weeks.

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bumbyyesterday at 9:08 PM

Something often overlooked in cost/schedule estimates is the nature of joint probability of actions slipping. Action A slips and causes action B to slip. I think software is tougher to estimate because the number of interfaces is often much higher, and sometimes more hidden, than in hardware.

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Scarblacyesterday at 9:13 PM

That's a factor four or five ir so, so still less than an order of magnitude.