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Controlling time. ( seminar ). Why to control?. Monitoring and analysis of project data should enable the project manager to address problems at an early stage and take advantages of opportunities; prevent problems rather than responding to them;
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Controlling time (seminar)
Why to control? Monitoring and analysis of project data should enable the project manager to • address problems at an early stage and • take advantages of opportunities; • prevent problems rather than responding to them; • communicate quickly and effectively: thusproject members will work with the same and up-to-date information, and can quickly deal with problems.
6 essential features of control systems • A plan must be made • This plan must be published • Once working, the activity being controlled must be measured • The measurements must then be compared with the plan • Any deviations must be reported to the appropriate person • A forecast of the results of any deviations must then be made, and corrective actions taken or a new plan must be made Barchart PNTs
Measurement of activities • The measurement should be appropriately precise • The measurement should be pertinent • The speed of collection of the information must be rapid compared with the timecycle of the system as a whole • Measurements need to be accurate or of consistent inaccuracy • The number of data processing points should be kept as small as possible
The measurement should be appropriately precise • Precision is positively correlated with measurement costs • PNT indicates the necessity of precision • Critical activities • Non-critical activities
The measurement should be pertinent • What use the collected data can be made
The speed of data collection… • Measurement must be taken frequently enough to allow useful action to be taken. • The longer the time for corrective actions to be taken, the lower frequency of measurement is acceptible. • Thus: the speed of data collection will increase toward the project’s ending.
Measurements need to be accurate or of consistent inaccuracy • Accuracy can be bought with increased cost. • Inaccurate but consistent measuring technique can be acceptable. • PNT: where is the low accuracy tolerable. • Accuracy and precision is NOT the same:Accuracy = degree of closeness to the true value (validity)Precision = degree to which repeated measurements leads to the same results (reliability).
The number of data processing points should be kept as small as possible Too much processing points would lead to: • delay in information use • distortions in the information
3 useful methods(the simplest is the best) • The bar (Gantt) chart • Re-analysis • Negative float
Activities time 1. 2. 3. 4. 5. 6. Gantt chart as a time control method(best for smaller projects) today
Re-analysis • In large and/or complex projects. • Taking the original network and inserting into the actualtimes instead of the expected durations. Sometimes new „delay activites” need to be built in. OR • Re-drawing the network leaving out all those activities that are complete and re-analyse the others.
Negative float • If the network is too large and complex. • Fix the end date, insert the actual durations and re-analyse the network (backward analysis). • Late activities will appear with negative float. There must be corrective actions taken.
Example Marketing research (survey) project. Estimation of activity durations: • Creating the SOW (formulating the research questions, budget etc). = 7 days • Collecting secondary information: • models = 15 days • empirics = 15 days • Planning the research = 7 days • Formulating the questionnaire = 14 days • Collecting data in 3 destinations form 100-100 people = 10 days each • Entering data = 2 days per one subsample • Analysing data = 6 days • Writing up the research report = 7 days • Presenting the results = 1 day
Reporting rules • Avoid recrimination (‘past is dead’). Take steps to avoid a recurrence of failure not to create a fuss. • Progress should be reported in the form: • not complete • How much time is required to complete the activity? • complete • PNT helps to identify problematic areas and distinguishes areas of authority but not remove any responsibility.
Forecasting with PNT • It enables predictions of resultant actions to be deduced from present or past actions.
Forecasting example with PNT • Total project time (TPT)of 1000 days. • After 400 days the planned network time for the completed activities is 350 days. • What is the expected time to finish the project? • What is the estimated time slip for the whole project? • Calculate the schedule performance index.
Solution • Originally expected time for the rest of the project: 1000-350=650 days • Form the past activities we can calculate how these days have to be recalculated if the performance is not changing: 400/350=8/7 • Current estimated time to complete: 650*(8/7)=743 • Current estimated TPT: 400+743=1143 • Total current estimated time slip: 1000-1143=-143 • Current schedule performance index: 350/400=0.875=87.5%
Reading • Textbook chapter 9
