Assignment 3 Question 1.2

I'm slightly confused by Question 1.2 in Assignment 3.

Firstly, it asks which can be completed in under 3 years. I assume this means Person Years, as providing more resource for the project will decrease the duration?

Secondly, according to my calculations none of the projects can be completed under 3 Person Years. Has anyone else come up with this answer? It seems a bit odd...

I have exactly the opposite. All my projects can be completed in less than 3 years. The difference in our answers, I figure, is size. I feel that since is measured in thousands of lines then System A size should be 28.557 and not 28557 ie divide by 1000. That said, I dont know if my calcs are correct though...

Some resources I have been playing with is
http://www.cs.odu.edu/~zeil/cs451/Lectures/04mgmt/costest/costest_htsu3.html
http://cost.jsc.nasa.gov/COCOMO.html.

What formula are you using? I also divided by 1000, rounding to 1 decimal place. So for "A" I have:

A = 2.4(28.5)^1.05 = 80.87pm

Plugging in 28.5 as a value into the program on http://cost.jsc.nasa.gov/COCOMO.html#COCOMO gives a similar answer.


EDIT:
Right, after doing some more reading online (Wikipedia in particular has a good summary) I found the following equation:
Development Time = cb(Effort Applied)^db [months]

The coefficients cb and db are given as the following:
Software project cb db
Organic 2.5 0.38
Semi-detached 2.5 0.35
Embedded 2.5 0.32

Plugging my result for "A" into this equation I get:
Time = 2.5(80.87)^0.38 = 13.27 months

So I guess this is the final equation to use? I can't find this anywhere in the textbook though?

My solution is similar. When applying the following:
effortInPersonMonths/12 = effortInPersonYears = (c(size/1000)^k)/12
tells me that none of the systems will take less than 3 years.

PubCrawler, as far as I understand it, you still need to apply the second formula to your answer. I'm going to do both and then specify in my answer that one set contains the effort in person months, the other is development time. Effort is fed into the development time calculation anyway, so at worst you're doing a bit of extra calculation that won't be marked. Rather that than lose a big chunk of your mark for this assignment.