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Controlling time. ( lecture & 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 opportunitie s; prevent problems rather than responding to them;
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Controlling time (lecture & 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 correctiveactions 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 acceptable. • 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 or the network itself • Re-analysis • Negative float
Activities time 1. 2. 3. 4. 5. 6. Gantt chart as a time control method(best for smaller projects) today
Example Marketing research (survey) project. Estimation of activity durations: • Creating the SOW (framework for the research). = 7 days • Collecting secondary information: • models = 15 days • empirics = 15 days • Planning the research = 6 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
Example After 30 days: • SOW is made in 7 days • Secondary research on models was finished in 14 days • Secondary research on empirics was finished in 18 days • Half of the research plan is written • No other activity is started
Re-analysis with PNT (or Gantt chart) • 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.
Example 2 (for networks) • Manufacturing project: The firm have to purchase two types of raw materials (A & B; procurement is centralised thus it is a single activity), and produce two different product parts from these (P1 and P2). These can be done separately. P2 has to put through an obligatory test, P1 do not. After both P1 and P2 are ready, the firm will assemble them with an externally bought P3 part to the final product. Project done. Create the WBS and identify tasks.
b 5 a 7 c 2 d 2 f 2 e 4 Example 2 The duration times for the activities (with activity labels): • (a) Raw materials procurement: 7 days • (b) P1 production: 5 days • (c) P2 production: 2 days • (d) P2 test: 2 days • (e) P3 procurement: 4 days • (f) Assembly: 2 days • Network? • TPT? a-b-f = 14 a-c-d-f = 13 a-e-f = 13 = TPT
Example 2: problems arise • After the project started, it became obvious that the testing facility will not be able to start the testing process in time, only two days later. • The P3 procurement is expected to be 1 day longer, too. • Re-analyse the project with the network. • Identify the new TPT. b 5 a 7 c 2 delay 2 d 2 f 2 e 5 a-b-f = 14 a-c-(delay)-d-f = 15 a-e-f = 14 = TPT
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.
0 0 0 1 1 b 5 1 b 5 0 a 7 c 2 delay 2 d 2 f 2 a 7 c 2 d 2 f 2 -1 -1 -1 -1 -1 e 5 e 4 0 Example 2: calculate floats and negative floats This will be discussed in a more sophisticated way on the following classes, after we learn more about the network diagrams.
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 • Planned total project time (PTPT)of 1000 days. • After 400 days (ATWP)the planned time for the work performed (PTWP) is 350 days. • What is the estimated time to complete (ETC)the project? • What is the estimated time slip for the whole project? • Calculate the schedule performance index(SPI).
Solution • Planned time to complete (PTC): PTPT – PTWP = 1000-350=650 days • From the past activities we can calculate how these days have to be recalculated if the performance is not changing: ATWP/PTWP = 400/350=8/7 • Current estimated time to complete (ETC): 650*(8/7)=743 • Current estimated TPT: 400+743=1143 • Total current estimated time slip: 1000-1143=-143 • Current schedule performance index (SPI): PTWP/ATWP=350/400=0.875=87.5%
Problem solving There is a project with a planned Total Project Time (TPT) of 120 days. The project consist of three non-overlapping work packages witha duration of 40-40 days each. After 20 days only 37.5% of the first work package is completed. Calculate thefollowing: • current schedule performance index (SPI) • total current estimated time slip • planned time to complete • current estimated time to complete (ETC) • current estimated Total Project Time (TPT)
Reading • Textbook chapter 9
