Guild of Project Controls: Compendium | Roles | Assessment | Certifications | Membership

Tips on using this forum..

(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?

(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.

Forecasting and Trending

2 replies [Last post]
Scott Parker
User offline. Last seen 11 years 35 weeks ago. Offline
Joined: 26 Jul 2012
Posts: 6
Groups: None

I currently am running projects that are fairly short in duration (3 months).  I progress daily and progress using Physical % Complete since I can measure units completed.  Since the duration of each project is short my CPI seems to be manic.  Up one week then down the next.  I was wondering if anyone can suggest a strategy to forecast and trend these types of project better.  Much appreciated.

 

Balance 

Replies

Rafael Davila
User offline. Last seen 2 weeks 19 hours ago. Offline
Joined: 1 Mar 2004
Posts: 5230

Usually you estimate your costs based on historical data averages. But each job is different and therefore you are in need to forecast in-progress jobs using individual job trends. Because job trends depend on individual job historical data only after about 60% of your job is done that trends and forecasting will be closer to final results.

Trending is a functionality embedded in software such as Spider Project. It shall be performed using the same CPM engine you use to actually manage your job, especially when using Monte Carlo Methods.

You got to live with some uncertainty, it is a fact of life. I suggest using statistical methods within your software to estimate your probabilities of success trends. Beware that Monte Carlo still behaves as stated above, it is dynamic and should be run periodically.

From Spider Project Help.

Success Probabilities Trends is a method of project performance analysis. Probabilities of achieving target project finish dates, target budget and target material consumption are analyzed in the course of project performance. Trends can be obtained for such parameters as project finish date, total cost, project cost components, materials, cost centers and material centers. Trends of these probabilities provide valuable information for project success estimates.

Enjoy the rollercoster ride, it is fun.

Best regards,

Rafael

Mike Testro
User offline. Last seen 17 weeks 4 days ago. Offline
Joined: 14 Dec 2005
Posts: 4418

Hi Scott

Accuracy of % complete estimation depends on the level of detail in the tasks on the programme.

If you have tasks longer than 10 working days with more than one trade or location involved your % complete will never be accurate.

Short tasks with one trade in one location and you will then have three choices each day 0% - 50% - 100%.

Better to have a few minor innacuracies than one great big one.

Best regards

Mike Testro