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CommodityQuant
Topic Author
Posts: 207
Joined: July 5th, 2007, 6:16 am

### Estimate the length of time to complete a project

I am a quant dev with a big C++ quant project and am charged with estimating how long it will take me to deliver. I have 3 days to produce the estimate.
I think that tentatively, management expect me to give a figure around the three months mark.
This project involves enhancing legacy code.
Can anyone give any guidance to resources on how to produce an estimate?  Of course, it's notoriously difficult to tell when a several-months project can be delivered.  It must be a common problem, and I'm sure there's a fair amount of literature on project
estimation but it would be good to see resources that are specifically oriented towards C++ quant projects rather than the completely
general case.
One thing that might be helpful might be info about how long various quantlib enhancements took.  This library is more similar to
quantlib than any other readily available library.  Any thoughts?  Thanks a lot.

CommodityQuant

snufkin
Posts: 40
Joined: January 25th, 2017, 9:05 am
Location: Cambridge

### Re: Estimate the length of time to complete a project

The ultimate guide to estimates like that is given by Joel Spolsky at https://www.joelonsoftware.com/2007/10/26/evidence-based-scheduling/; the previous version, though he says it's obsolete, is what you want to see: https://www.joelonsoftware.com/2000/03/29/painless-software-schedules/

In brief, you spend a day splitting the project into tasks, preferably under a day each. Then (another day), you assign an effort estimate to each one and sum those up. Then you spend a day considering the presentation of the estimate. There's absolutely nothing specific about C++ or quant case, it's just that the tasks will be different.

Having said all that, consider what you lose if the estimate you give is one year? Two years? One month? Six months? In a sense, that's more of an exercise in setting up expectations. If you have an expectation of three months, do you need to challenge it? Are you okay with shipping something that's a result of three months worth of work, and claiming that's what's expected?

CommodityQuant
Topic Author
Posts: 207
Joined: July 5th, 2007, 6:16 am

### Re: Estimate the length of time to complete a project

snufkin, Many thanks for some very useful ideas and reference.

CommodityQuant

ppauper
Posts: 63403
Joined: November 15th, 2001, 1:29 pm

### Re: Estimate the length of time to complete a project

I'm guessing that if you estimate 3 months and it takes 4, it looks like you have mismanaged the project, but if you estimate 6 months and it takes 4, you're a hero for bringing it in early
As snufkin said, managing expectations.

DominicConnor
Posts: 11678
Joined: July 14th, 2002, 3:00 am

### Re: Estimate the length of time to complete a project

Timescales are important, but also the schedule and expectations you set...

I've long advocated  "Continuous Visible Productivity", in other words structuring your work so that management regularly get to see progress. Big deep dives where nothing seems to happen are bad for your survival and bonus.

I'd also counsel you to run http://www.gimpel.com/html/index.htm PC Lint.
It will give a long list of bugs, potential bugs and general shit. This is important because you're dealing with old code. This is a thing to show to management to let them know how much grind ther is in the task. They won't read it,. but it sets an agenda...
Most of debugging is finding the bug, fixzing is easier usually. That means you have a list of defects that you can tick off and show progress, even better, this isn't just for show, you are genuinely makling things better.

ISayMoo
Posts: 183
Joined: September 30th, 2015, 8:30 pm

### Re: Estimate the length of time to complete a project

snufkin wrote:
The ultimate guide to estimates like that is given by Joel Spolsky at https://www.joelonsoftware.com/2007/10/26/evidence-based-scheduling/; the previous version, though he says it's obsolete, is what you want to see: https://www.joelonsoftware.com/2000/03/29/painless-software-schedules/

In brief, you spend a day splitting the project into tasks, preferably under a day each. Then (another day), you assign an effort estimate to each one and sum those up.

And then you multiply the estimate by x >= 1.5.

Cuchulainn
Posts: 51710
Joined: July 16th, 2004, 7:38 am
Location: Amsterdam
Contact:

### Re: Estimate the length of time to complete a project

With estimation it is always junk in junk out. So if you cannot estimate ask for a prototype project to get a feel for the complexity.
Developers love to please, so they always forget pre and postprocessing in their estimates.

I have found 3-point estimation to be useful, especially for binding fixed price projects

https://en.wikipedia.org/wiki/Three-point_estimation
http://www.datasimfinancial.com

“Continuous improvement is better than delayed perfection.” Samuel Langhorne Clemens

Cuchulainn
Posts: 51710
Joined: July 16th, 2004, 7:38 am
Location: Amsterdam
Contact:

### Re: Estimate the length of time to complete a project

One thing that might be helpful might be info about how long various quantlib enhancements took.  This library is more similar to quantlib than any other readily available library.  Any thoughts?

Can you give some use cases, features used, documentation(yes), OOP, templates, design patterns, inheritance etc.

Do you have design blueprints or do you have to wade in code to do reverse engineering? Do you have a good understanding of the current system?

It is not far-fetched but one can spend 4.5 days per week just 'thinking' about the ramifications of adding a new feature and .5 days coding up.

Project estimation time increases exponentially IMO when

1. Deep inheritance class libraries; many classes down the tree are semantically incorrect.
2. Multiple inheritance
3. No blueprints
4. Undocumented design patterns
5. Wrong pattern(Observer, Singleton)
6. Over-engineering

Are we in the era "OOP legacy software revisited".
Last edited by Cuchulainn on June 1st, 2017, 9:35 am
http://www.datasimfinancial.com

“Continuous improvement is better than delayed perfection.” Samuel Langhorne Clemens

Cuchulainn
Posts: 51710
Joined: July 16th, 2004, 7:38 am
Location: Amsterdam
Contact:

### Re: Estimate the length of time to complete a project

snufkin wrote:
The ultimate guide to estimates like that is given by Joel Spolsky at https://www.joelonsoftware.com/2007/10/26/evidence-based-scheduling/; the previous version, though he says it's obsolete, is what you want to see: https://www.joelonsoftware.com/2000/03/29/painless-software-schedules/

In brief, you spend a day splitting the project into tasks, preferably under a day each. Then (another day), you assign an effort estimate to each one and sum those up. Then you spend a day considering the presentation of the estimate. There's absolutely nothing specific about C++ or quant case, it's just that the tasks will be different.

Having said all that, consider what you lose if the estimate you give is one year? Two years? One month? Six months? In a sense, that's more of an exercise in setting up expectations. If you have an expectation of three months, do you need to challenge it? Are you okay with shipping something that's a result of three months worth of work, and claiming that's what's expected?

hmmm.. very sweeping statements
Personally, Barry Boehm's book on Software Economics and Ed Yourdon's Deathmarch add some needed gravitas.
http://www.datasimfinancial.com

“Continuous improvement is better than delayed perfection.” Samuel Langhorne Clemens

rmax
Posts: 5804
Joined: December 8th, 2005, 9:31 am

### Re: Estimate the length of time to complete a project

Late to the party on this one. Agree with much of what is said above. What I think really helps with any form of estimate is treat it as a market and make a two way price. What price would you make if it was 1 USD a day above or below you price. The spread tends to be a good indication of the accuracy of the information you have to hand.

Management expectation is important. Around 4 years ago I was asked to price up a large programme of work. I came up with a toppy estimate around 2 years to get the work completed and they thought they could get it done in a year. I was laughed off the programme and replaced. The person that took over was replaced around 2 years ago. They are still going strong hoping to deliver early next year...

snufkin
Posts: 40
Joined: January 25th, 2017, 9:05 am
Location: Cambridge

### Re: Estimate the length of time to complete a project

rmax wrote:
Management expectation is important. Around 4 years ago I was asked to price up a large programme of work. I came up with a toppy estimate around 2 years to get the work completed and they thought they could get it done in a year. I was laughed off the programme and replaced. The person that took over was replaced around 2 years ago. They are still going strong hoping to deliver early next year...

Back when I was in the software outsourcing business, that was exactly our favourite type of clients: "We want to build X — Okay, that's 1 year and so much — But there's this company, they do it cheaper in half the time — Oh, really? Good luck then — (a year later) You know, we're still struggling to deliver, how much will it be to finish this project?"