暨南大学《项目管理》chapter5estimatingprojecttimesandcosts

1、管理学院 School of Management,佟瑞 Edward Tong， MPM，MBA,2020/12/19,1,Edward TongCopyright reserved Jinan University,52,Where We Are Now,53,Estimating Projects,Estimating The process of forecasting or approximating the time and cost of completing project deliverables. The task of balancing expectations of

2、stakeholders and need for control while the project is implemented. Types of Estimates Top-down (macro) estimates: analogy, group consensus, or mathematical relationships Bottom-up (micro) estimates: estimates of elements of the work breakdown structure,54,Why Estimating Time and Cost Are Important,

3、EXHIBIT 5.1,To support good decisions. To schedule work. To determine how long the project should take and its cost. To determine whether the project is worth doing. To develop cash flow needs. To determine how well the project is progressing. To develop time-phased budgets and establish the project

4、 baseline.,55,Factors Influencing the Quality of Estimates,Quality of Estimates,ProjectDuration,People,Project Structure and Organization,PaddingEstimates,OrganizationCulture,Other (Nonproject)Factors,Planning Horizon,56,Estimating Guidelines for Times, Costs, and Resources,Have people familiar with

5、 the tasks make the estimate. Use several people to make estimates. Base estimates on normal conditions, efficient methods, and a normal level of resources. Use consistent time units in estimating task times. Treat each task as independent, dont aggregate. Dont make allowances for contingencies. Add

6、ing a risk assessment helps avoid surprises to stakeholders.,57,Top-Down versus Bottom-Up Estimating,Top-Down Estimates Are usually are derived from someone who uses experience and/or information to determine the project duration and total cost. Are made by top managers who have little knowledge of

7、the processes used to complete the project. Bottom-Up Approach Can serve as a check on cost elements in the WBS by rolling up the work packages and associated cost accounts to major deliverables at the work package level.,58,Top-Down versus Bottom-Up Estimating,TABLE 5.1,59,Estimating Projects: Pref

8、erred Approach,Make rough top-down estimates. Develop the WBS/OBS. Make bottom-up estimates. Develop schedules and budgets. Reconcile differences between top-down and bottom-up estimates,510,Top-Down Approaches for Estimating Project Times and Costs,Consensus methods Ratio methods Apportion method F

9、unction point methods for software and system projects Learning curves,511,Apportion Method of Allocating Project Costs Using the Work Breakdown Structure,FIGURE 5.1,512,Simplified Basic Function Point Count Process for a Prospective Project or Deliverable,TABLE 5.2,513,Example: Function Point Count

10、 Method,TABLE 5.3,514,Bottom-Up Approaches for Estimating Project Times and Costs,Template methods Parametric procedures applied to specific tasks Range estimates for the WBS work packages Phase estimating: A hybrid,515,Support Cost Estimate Worksheet,FIGURE 5.2,516,Phase Estimating over Product Lif

11、e Cycle,FIGURE 5.3,517,Top-Down and Bottom-Up Estimates,FIGURE 5.4,518,Level of Detail,Level of detail is different for different levels of management. Level of detail in the WBS varies with the complexity of the project. Excessive detail is costly. Fosters a focus on departmental outcomes Creates u

12、nproductive paperwork Insufficient detail is costly. Lack of focus on goals Wasted effort on nonessential activities,519,Types of Costs,Direct Costs Costs that are clearly chargeable to a specific work package. Labor, materials, equipment, and other Direct (Project) Overhead Costs Costs incurred tha

13、t are directly tied to an identifiable project deliverable or work package. Salary, rents, supplies, specialized machinery General and Administrative Overhead Costs Organization costs indirectly linked to a specific package that are apportioned to the project,520,Contract Bid Summary Costs,FIGURE 5.

14、5,521,Three Views of Cost,FIGURE 5.6,522,Refining Estimates,Reasons for Adjusting Estimates Interaction costs are hidden in estimates. Normal conditions do not apply. Things go wrong on projects. Changes in project scope and plans. Adjusting Estimates Time and cost estimates of specific activities a

15、re adjusted as the risks, resources, and situation particulars become more clearly defined.,523,Creating a Database for Estimating,FIGURE 5.7,524,Key Terms,Apportionment methods Bottom-up estimates Contingency funds Delphi method Direct costs Function points Learning curves,Overhead costs Padding es

16、timates Phase estimating Range estimating Ratio methods Template method Time and cost databases,525,WBS Figure,TABLE 5.4,526,Learning Curves Unit Values,TABLE A5.1,527,Learning Curves Cumulative Values,TABLE A5.2,2020/12/19,Edward Tong2008 copy reserved Jinan University,28,1,The process of forecasti

17、ng or approximating the time and cost of completing project deliverables is called cA.BudgetingB.PredictingC.EstimatingD.PlanningE.Guesstimating,2020/12/19,Edward Tong2008 copy reserved Jinan University,29,2,In practice, estimating processes are frequently classified asaA.Top down/bottom upB.Rough/p

18、olishedC.Precise/order of magnitudeD.Draft/finalE.Both A and B are correct,2020/12/19,Edward Tong2008 copy reserved Jinan University,30,3,A typical statement in actual practice is that estimates should have a probability of being met _ of the time.cA.100%B.98%C.95%D.90%E.80%,2020/12/19,Edward Tong20

19、08 copy reserved Jinan University,31,4,A good starting point for developing time and cost estimates isaA.Past experienceB.Work packagesC.Task analysisD.Time and motion studiesE.Work breakdown structure,5,2020/12/19,Edward Tong2008 copy reserved Jinan University,32,Which of the following is not one o

20、f the factors that need to be considered to improve quality of estimates for project times and costs?dA.Planning horizonB.PeopleC.Padding estimatesD.ProfitE.Project structure,6,2020/12/19,Edward Tong2008 copy reserved Jinan University,33,Ed is looking over the actual results of projects and comparin

21、g them to what was estimated. He notices that projects that took six months or longer to complete were noticeably more off the estimates. Which of the following factors is he recognizing?bA.Padding estimatesB.Planning horizonC.Project structureD.PeopleE.Organization culture,7,2020/12/19,Edward Tong2

22、008 copy reserved Jinan University,34,Janet is forecasting how much money her department needs to support a new project. She estimates that two people and $25,000 in expenses will cover her needs. Because management typically insists on reducing forecasts by 20 percent, she increases her estimates t

23、o allow for that reduction. Which of the following factors is illustrated in this situation? aA.Padding estimatesB.Planning horizonC.Project structureD.PeopleE.Organization culture,8,2020/12/19,Edward Tong2008 copy reserved Jinan University,35,Which of the following is a good condition for top-down

24、estimating?dA.Cost and time importantB.Fixed price contractC.Customer wants detailsD.Internal, small projectE.All of these are good conditions for top-down estimating,9,2020/12/19,Edward Tong2008 copy reserved Jinan University,36,Which of the following is a good condition for bottom-up estimating?cA

25、.Strategic decision makingB.Internal, small projectC.Fixed price contractD.High uncertaintyE.Both C and D are good conditions for bottom-up estimating,10,2020/12/19,Edward Tong2008 copy reserved Jinan University,37,Top-down estimates are most likely to occur during the _ phase.aA.ConceptB.PlanningC.

26、ExecutionD.DeliveryE.All of these are equally likely,11,2020/12/19,Edward Tong2008 copy reserved Jinan University,38,_ estimates are most likely to use low cost, efficient methods.dA.ApportionB.RatioC.Top-downD.Bottom-upE.All of these are equally likely,12,2020/12/19,Edward Tong2008 copy reserved Ji

27、nan University,39,Which of the following methods is not considered a top-down approach to estimating project time and cost?bA.RatioB.TemplateC.ApportionD.Function pointE.Learning curve,13,2020/12/19,Edward Tong2008 copy reserved Jinan University,40,Jose is forecasting project time and cost for const

28、ructing a new building by multiplying the total square footage by a given dollar amount. Which of the following methods is he using?aA.RatioB.TemplateC.ApportionD.Function pointE.Learning curve,14,2020/12/19,Edward Tong2008 copy reserved Jinan University,41,Sean is forecasting the time and cost of d

29、eveloping a customized software program by looking at the number of inputs, outputs, inquires, files, and interfaces. Which of the following methods is he using?dA.RatioB.TemplateC.ApportionD.Function pointE.Learning curve,15,2020/12/19,Edward Tong2008 copy reserved Jinan University,42,Laura is fore

30、casting the time and cost of developing an intranet for a new customer. Her department has completed six such intranets for customers during the last two years. Although the proposed system is about the same size as the others she estimates that it will take about 10 percent less time and money. Whi

31、ch of the following methods is she using?eA.RatioB.TemplateC.ApportionD.Function pointE.Learning curve,16,2020/12/19,Edward Tong2008 copy reserved Jinan University,43,Learning curves are more likely to apply in situations where most of the costs arebA.MaterialsB.LaborC.OverheadD.Evenly spread over m

32、aterials, labor, and overheadE.All of these are equally likely situations for learning curves,17,2020/12/19,Edward Tong2008 copy reserved Jinan University,44,Which of the following is not one of the bottom-up approaches to estimating project time and cost?A.Parametric procedures applied to specific

33、tasksB.Estimates for the WBS work packages cC.Learning curveD.Template methodE.All of these are bottom-up approaches,18,2020/12/19,Edward Tong2008 copy reserved Jinan University,45,The approach that begins with a top-down estimate for the project and then refines estimates as the project is implemen

34、ted is known as _ method.dA.Function pointB.TemplateC.Learning curveD.Phase estimatingE.Apportion,19,2020/12/19,Edward Tong2008 copy reserved Jinan University,46,Which of the following would be the best method for projects where the final product is not known and the uncertainty is very large?dA.Fun

35、ction pointB.TemplateC.Learning curveD.Phase estimatingE.Apportion,20,2020/12/19,Edward Tong2008 copy reserved Jinan University,47,The accuracy of top-down estimates will typically be in the range ofcA.Minus 50% to plus 50%B.Minus 0% to plus 75%C.Minus 20% to plus 60%D.Minus 35% to plus 35%E.Minus 1

36、0% to plus 30%,21,2020/12/19,Edward Tong2008 copy reserved Jinan University,48,The accuracy of bottom-up estimates will typically be in the range ofeA.Minus 50% to plus 50%B.Minus 0% to plus 75%C.Minus 20% to plus 60%D.Minus 35% to plus 35%E.Minus 10% to plus 30%,22,2020/12/19,Edward Tong2008 copy r

37、eserved Jinan University,49,The cost to prepare bottom-up estimates will typically run how much more than the costs to prepare the top-down estimates? cA.About the sameB.About twice as muchC.About three times as muchD.About four times as muchE.About five times as much,23,2020/12/19,Edward Tong2008 c

38、opy reserved Jinan University,50,Typical kinds of costs found in a project includeeA.Direct costsB.Project overhead costsC.General and administrative costsD.Only A and B are includedE.A, B, and C are all included,24,2020/12/19,Edward Tong2008 copy reserved Jinan University,51,Project costs are typic

39、ally viewed from all of the following except:bA.ScheduledB.SunkC.ActualD.CommittedE.All of these are correct,25,2020/12/19,Edward Tong2008 copy reserved Jinan University,52,Which of the following would be considered a direct project cost?eA.LaborB.MaterialsC.EquipmentD.Both A and B are direct costsE

40、.A, B, and C are all considered direct costs,26,2020/12/19,Edward Tong2008 copy reserved Jinan University,53,Which of the following is not one of the recommended guidelines for developing useful work package estimates?A.Estimates should be made by those responsible for the work dB.Use several people

41、 to estimate the same workC.Estimates should be based on normal conditionsD.Estimates should include a normal level of contingencyE.Estimates should be independent of other projects,27,2020/12/19,Edward Tong2008 copy reserved Jinan University,54,Companies like Boeing, Kodak, and IBM are using which

42、of the following for improving the estimating process?dA.Adjusting estimates based on individual forecasting abilitiesB.Benchmarking using the experience of other companiesC.Using time and motion studiesD.Creating historical databases of previous projectsE.All of these are correct,28,2020/12/19,Edwa

43、rd Tong2008 copy reserved Jinan University,55,Reasons why estimating time and cost are important include all of the following except:eA.To schedule workB.To determine how long the project should take and costC.To develop cash flow needsD.To determine how well the project is progressingE.All of the a

44、bove are valid reasons,29,2020/12/19,Edward Tong2008 copy reserved Jinan University,56,In a learning curve, the improvement ratio is applied to which of the following items?bA.Direct materialsB.Direct laborC.OverheadD.Both A and B are correctE.A, B, and C are all correct,30,2020/12/19,Edward Tong200

45、8 copy reserved Jinan University,57,The bottom-up approach for estimating times and costs that uses costs from past projects that were similar to the current project is known as:bA.Detailed WBS work package estimatesB.Template methodC.Function point methodD.Time-phased cost estimatesE.Phase estimating,31,2020/12/19,Edward Tong2008 copy reserved Jinan University,58,Which of the follow top-down methods is used when projects closely follow