Presentation is loading. Please wait.

Presentation is loading. Please wait.

A – 1 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decision Making A For Operations Management, 9e by Krajewski/Ritzman/Malhotra.

Similar presentations


Presentation on theme: "A – 1 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decision Making A For Operations Management, 9e by Krajewski/Ritzman/Malhotra."— Presentation transcript:

1 A – 1 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decision Making A For Operations Management, 9e by Krajewski/Ritzman/Malhotra © 2010 Pearson Education PowerPoint Slides by Jeff Heyl

2 A – 2 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Break-Even Analysis Evaluating Services or Products  Is the predicted sales volume of the service or product sufficient to break even (neither earning a profit nor sustaining a loss)?  How low must the variable cost per unit be to break even, based on current prices and sales forecasts?  How low must the fixed cost be to break even?  How do price levels affect the break-even quantity?

3 A – 3 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Break-Even Analysis Break-even analysis is based on the assumption that all costs related to the production of a specific service or product can be divided into two categories: variable costs and fixed costs Variable cost, c, is the portion of the total cost that varies directly with volume of output If Q = the number of customers served or units produced per year, total variable cost = cQ Fixed cost, F, is the portion of the total cost that remains constant regardless of changes in levels of output

4 A – 4 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Break-Even Analysis By setting revenue equal to total cost pQ = F + cQ Q = F p - c So Total cost = F + cQ Total revenue = pQ

5 A – 5 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Finding the Break-Even Quantity EXAMPLE A.1 A hospital is considering a new procedure to be offered at $200 per patient. The fixed cost per year would be $100,000, with total variable costs of $100 per patient. What is the break-even quantity for this service? Use both algebraic and graphic approaches to get the answer. SOLUTION The formula for the break-even quantity yields Q = F p - c = 1,000 patients = 100, – 100

6 A – 6 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Finding the Break-Even Quantity To solve graphically we plot two lines: one for costs and one for revenues Begin by calculating costs and revenues for two different output levels The following table shows the results for Q = 0 and Q = 2,000 Quantity (patients) ( Q ) Total Annual Cost ($) (100, Q ) Total Annual Revenue ($) (200 Q ) 0100,0000 2,000300,000400,000 Draw the cost line through points (0, 100,000) and (2,000, 300,000) Draw the revenue line through (0, 0) and (2,000, 400,000)

7 A – 7 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Finding the Break-Even Quantity Total annual costs Fixed costs Break-even quantity Profits Loss Patients (Q) Dollars (in thousands) 400 – 300 – 200 – 100 – 0 – |||| (2000, 300) Total annual revenues The two lines intersect at 1,000 patients, the break-even quantity FIGURE A.1 – Graphic Approach to Break-Even Analysis (2000, 400)

8 A – 8 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.1 The Denver Zoo must decide whether to move twin polar bears to Sea World or build a special exhibit for them and the zoo. The expected increase in attendance is 200,000 patrons. The data are: Revenues per Patron for Exhibit Gate receipts$4 Concessions$5 Licensed apparel$15 Estimated Fixed Costs Exhibit construction$2,400,000 Salaries$220,000 Food$30,000 Estimated Variable Costs per Person Concessions$2 Licensed apparel $9 Is the predicted increase in attendance sufficient to break even?

9 A – 9 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.1 Q TR = pQTC = F + cQ 0$0$2,650, ,000$6,000,000$5,400,000 7 – 6 – 5 – 4 – 3 – 2 – 1 – 0 – |||||| Cost and revenue (millions of dollars) Q (thousands of patrons) Total Cost Total Revenue Where p = = $24 F = 2,400, , ,000 = $2,650,000 c = = $11

10 A – 10 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.1 Q TR = pQTC = F + cQ 0$0$2,650, ,000$6,000,000$5,400,000 Where p = = $24 F = 2,400, , ,000 = $2,650,000 c = = $11 Algebraic solution of Denver Zoo problem pQ = F + cQ 24 Q = 2,650, Q 13 Q = 2,650,000 Q = 203,846

11 A – 11 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Sensitivity Analysis EXAMPLE A.2 If the most pessimistic sales forecast for the proposed service in Figure A.1 were 1,500 patients, what would be the procedure’s total contribution to profit and overhead per year? SOLUTION The graph shows that even the pessimistic forecast lies above the break-even volume, which is encouraging. The product’s total contribution, found by subtracting total costs from total revenues, is 200(1,500) – [100, (1,500)] pQ – ( F + cQ ) = =$50,000

12 A – 12 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Evaluating Processes Choices must be made between two processes or between an internal process and buying services or materials on the outside We assume that the decision does not affect revenues The analyst finds the quantity for which the total costs for two alternatives are equal

13 A – 13 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Evaluating Processes Let F b equal the fixed cost (per year) of the buy option, F m equal the fixed cost of the make option, c b equal the variable cost (per unit) of the buy option, and c m equal the variable cost of the make option The total cost to buy is F b + c b Q and the total cost to make is F m + c m Q To find the break-even quantity, we set the two cost functions equal and solve for Q : F b + c b Q = F m + c m Q Q = F m – F b c b – c m

14 A – 14 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Break-Even Analysis for Make-or-Buy Decisions A fast-food restaurant featuring hamburgers is adding salads to the menu The price to the customer will be the same Fixed costs are estimated at $12,000 and variable costs totaling $1.50 per salad Preassembled salads could be purchased from a local supplier at $2.00 per salad Preassembled salads would require additional refrigeration with an annual fixed cost of $2,400 Expected demand is 25,000 salads per year What is the break-even quantity? EXAMPLE A.3

15 A – 15 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Break-Even Analysis for Make-or-Buy Decisions SOLUTION The formula for the break-even quantity yields the following: Q = F m – F b c b – c m = 19,200 salads = 12,000 – 2, – 1.5 Figure A.2 shows the solution from OM Explorer’s Break- Even Analysis Solver. The break-even quantity is 19,200 salads. As the 25,000-salad sales forecast exceeds this amount, the make option is preferred. Only if the restaurant expected to sell fewer than 19,200 salads would the buy option be better.

16 A – 16 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Break-Even Analysis for Make-or-Buy Decisions FIGURE A.2 – Break-Even Analysis Solver of OM Explorer for Example A.3

17 A – 17 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.2 F m – F b c b – c m Q = = $150,000 At what volume should the Denver Zoo be indifferent between buying special sweatshirts from a supplier or have zoo employees make them? = $300,000 – $0 $9 – $7 BuyMake Fixed costs$0$300,000 Variable costs$9$7

18 A – 18 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Preference Matrix A Preference Matrix is a table that allows you to rate an alternative according to several performance criteria The criteria can be scored on any scale as long as the same scale is applied to all the alternatives being compared Each score is weighted according to its perceived importance, with the total weights typically equaling 100 The total score is the sum of the weighted scores (weight × score) for all the criteria and compared against scores for alternatives

19 A – 19 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. EXAMPLE A.4 The following table shows the performance criteria, weights, and scores (1 = worst, 10 = best) for a new thermal storage air conditioner. If management wants to introduce just one new product and the highest total score of any of the other product ideas is 800, should the firm pursue making the air conditioner? Evaluating an Alternative Performance CriterionWeight (A)Score (B) Weighted Score (A  B) Market potential Unit profit margin Operations compatibility Competitive advantage Investment requirements10220 Project risk5420 Weighted score =750

20 A – 20 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. SOLUTION Because the sum of the weighted scores is 750, it falls short of the score of 800 for another product. This result is confirmed by the output from OM Explorer’s Preference Matrix Solver in Figure A.3. Evaluating an Alternative FIGURE A.3 – Preference Matrix Solver for Example A.4 Total750

21 A – 21 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.3 Performance CriterionWeightScoreWeighted Score Market potential105 Unit profit margin308 Operations compatibility2010 Competitive advantage257 Investment requirements103 Project risk54 Total weighted score =

22 A – 22 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.3 Repeat this process for each alternative – pick the one with the largest weighted score Performance CriterionWeightScoreWeighted Score Market potential105 Unit profit margin308 Operations compatibility2010 Competitive advantage257 Investment requirements103 Project risk54 Total weighted score =

23 A – 23 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Criticisms Requires the manager to state criterion weights before examining alternatives, but they may not know in advance what is important and what is not Allows one very low score to be overridden by high scores on other factors May cause managers to ignore important signals

24 A – 24 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decision theory is a general approach to decision making when the outcomes associated with alternatives are in doubt A manager makes choices using the following process: Decision Theory 1.List a reasonable number of feasible alternatives 2.List the events (states of nature) 3.Calculate the payoff table showing the payoff for each alternative in each event 4.Estimate the probability of occurrence for each event 5.Select the decision rule to evaluate the alternatives

25 A – 25 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decision Making Under Certainty The simplest solution is when the manager knows which event will occur Here the decision rule is to pick the alternative with the best payoff for the known event

26 A – 26 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decisions Under Certainty EXAMPLE A.5 A manager is deciding whether to build a small or a large facility Much depends on the future demand Demand may be small or large Payoffs for each alternative are known with certainty What is the best choice if future demand will be low? Possible Future Demand AlternativeLowHigh Small facility Large facility Do nothing00

27 A – 27 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decisions Under Certainty SOLUTION The best choice is the one with the highest payoff For low future demand, the company should build a small facility and enjoy a payoff of $200,000 Under these conditions, the larger facility has a payoff of only $160,000 Possible Future Demand AlternativeLowHigh Small facility Large facility Do nothing00

28 A – 28 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Can list the possible events but can not estimate the probabilities Decision Making Under Uncertainty 1.Maximin: The best of the worst, a pessimistic approach 2.Maximax: The best of the best, an optimistic approach 3.Laplace: The alternative with the best weighted payoff assuming equal probabilities 4.Minimax Regret: Minimizing your regret (also pessimistic)

29 A – 29 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decisions Under Uncertainty EXAMPLE A.6 Reconsider the payoff matrix in Example A.5. What is the best alternative for each decision rule? SOLUTION a.Maximin. An alternative’s worst payoff is the lowest number in its row of the payoff matrix, because the payoffs are profits. The worst payoffs ($000) are AlternativeWorst Payoff Small facility200 Large facility160 The best of these worst numbers is $200,000, so the pessimist would build a small facility

30 A – 30 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decisions Under Uncertainty b.Maximax. An alternative’s best payoff ($000) is the highest number in its row of the payoff matrix, or AlternativeBest Payoff Small facility270 Large facility800 The best of these best numbers is $800,000, so the optimist would build a large facility

31 A – 31 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decisions Under Uncertainty c.Laplace. With two events, we assign each a probability of 0.5. Thus, the weighted payoffs ($000) are The best of these weighted payoffs is $480,000, so the realist would build a large facility 0.5(200) + 0.5(270) = (160) + 0.5(800) = 480 AlternativeWeighted Payoff Small facility Large facility

32 A – 32 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decisions Under Uncertainty d.Minimax Regret. If demand turns out to be low, the best alternative is a small facility and its regret is 0 (or 200 – 200). If a large facility is built when demand turns out to be low, the regret is 40 (or 200 – 160). Regret AlternativeLow DemandHigh Demand Maximum Regret Small facility200 – 200 = 0800 – 270 = Large facility200 – 160 = – 800 = 040 The column on the right shows the worst regret for each alternative. To minimize the maximum regret, pick a large facility. The biggest regret is associated with having only a small facility and high demand.

33 A – 33 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.4 Fletcher (a realist), Cooper (a pessimist), and Wainwright (an optimist) are joint owners in a company. They must decide whether to make Arrows, Barrels, or Wagons. The government is about to issue a policy and recommendation on pioneer travel that depends on whether certain treaties are obtained. The policy is expected to affect demand for the products; however it is impossible at this time to assess the probability of these policy “events.” The following data are available: Payoffs (Profits) Alternative Land Routes No treaty Land Routes Treaty Sea Routes Only Arrows$840,000$440,000$190,000 Barrels$370,000$220,000$670,000 Wagons$25,000$1,150,000($25,000)

34 A – 34 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.4 Fletcher (a realist), Cooper (a pessimist), and Wainwright (an optimist) are joint owners in a company. They must decide whether to make Arrows, Barrels, or Wagons. The government is about to issue a policy and recommendation on pioneer travel that depends on whether certain treaties are obtained. The policy is expected to affect demand for the products; however it is impossible at this time to assess the probability of these policy “events.” The following data are available: Payoffs (Profits) Alternative Land Routes No treaty Land Routes Treaty Sea Routes Only Arrows$840,000$440,000$190,000 Barrels$370,000$220,000$670,000 Wagons$25,000$1,150,000($25,000)

35 A – 35 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.4 Which product would be favored by Fletcher (realist)? Which product would be favored by Cooper (pessimist)? Which product would be favored by Wainwright (optimist)? What is the minimax regret solution? The short answers are: Payoffs (Profits) Alternative Land Routes No treaty Land Routes Treaty Sea Routes Only Arrows$840,000$440,000$190,000 Barrels$370,000$220,000$670,000 Wagons$25,000$1,150,000($25,000) Fletcher (realist – Laplace) would choose arrows Cooper (pessimist – Maximin) would choose barrels Wainwright (optimist – Maximax) would choose wagons The Minimax Regret solution is arrows

36 A – 36 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decisions Under Risk The manager can list the possible events and estimate their probabilities The manager has less information than decision making under certainty, but more information than with decision making under uncertainty The expected value rule is widely used This rule is similar to the Laplace decision rule, except that the events are no longer assumed to be equally likely

37 A – 37 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decisions Under Risk EXAMPLE A.7 Reconsider the payoff matrix in Example A.5. For the expected value decision rule, which is the best alternative if the probability of small demand is estimated to be 0.4 and the probability of large demand is estimated to be 0.6? SOLUTION The expected value for each alternative is as follows: Possible Future Demand AlternativeSmallLarge Small facility Large facility (200) + 0.6(270) = (160) + 0.6(800) = 544 AlternativeExpected Value Small facility Large facility

38 A – 38 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.5 For Fletcher, Cooper, and Wainwright, find the best decision using the expected value rule. The probabilities for the events are given below. What alternative has the best expected results? Payoffs (Profits) Alternative Land Routes No treaty Land Routes Treaty Sea Routes Only Arrows$840,000$440,000$190,000 Barrels$370,000$220,000$670,000 Wagons$25,000$1,150,000($25,000) (0.50)(840,000) +(0.30)(440,000) +(0.20)(190,000)= 590,000 (0.50)(370,000)+(0.30)(220,000) + (0.20)(670,000)= 385,000 (0.50)(25,000)+(0.30)(1,150,000)+(0.20)(-25,000)= 352,500 Alternative Land routes, No Treaty (0.50) Land Routes, Treaty Only (0.30) Sea routes, Only (0.20) Expected Value Arrows Barrels Wagons

39 A – 39 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Are schematic models of available alternatives and possible consequences Are useful with probabilistic events and sequential decisions Decision Trees Square nodes represent decisions Circular nodes represent events Events leaving a chance node are collectively exhaustive

40 A – 40 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Conditional payoffs for each possible alternative-event combination shown at the end of each combination Draw the decision tree from left to right Calculate expected payoff to solve the decision tree from right to left Decision Trees

41 A – 41 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Payoff 1 Payoff 2 Payoff 3 Alternative 3 Alternative 4 Alternative 5 Payoff 1 Payoff 2 Payoff 3 E 1 & Probability E 2 & Probability E 3 & Probability Alternative 1 Alternative 2 E 2 & Probability E 3 & Probability E 1 & Probability Payoff 1 Payoff 2 1st decision 1 Possible 2nd decision 2 Decision Trees = Event node = Decision node E i = Event i P(E i )= Probability of event i FIGURE A.4 – A Decision Tree Model

42 A – 42 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decision Trees After drawing a decision tree, we solve it by working from right to left, calculating the expected payoff for each of its possible paths 1.For an event node, we multiply the payoff of each event branch by the event’s probability and add these products to get the event node’s expected payoff 2.For a decision node, we pick the alternative that has the best expected payoff

43 A – 43 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decision Trees Various software is available for drawing and/or analyzing decision trees, including  PowerPoint can be used to draw decision trees, but does not have the capability to analyze the decision tree  POM with Windows  SmartDraw  PrecisionTree decision analysis from Palisade Corporation  TreePlan

44 A – 44 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree EXAMPLE A.8 A retailer will build a small or a large facility at a new location Demand can be either small or large, with probabilities estimated to be 0.4 and 0.6, respectively For a small facility and high demand, not expanding will have a payoff of $223,000 and a payoff of $270,000 with expansion For a small facility and low demand the payoff is $200,000 For a large facility and low demand, doing nothing has a payoff of $40,000 The response to advertising may be either modest or sizable, with their probabilities estimated to be 0.3 and 0.7, respectively For a modest response the payoff is $20,000 and $220,000 if the response is sizable For a large facility and high demand the payoff is $800,000

45 A – 45 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree SOLUTION The decision tree in Figure A.5 shows the event probability and the payoff for each of the seven alternative-event combinations. The first decision is whether to build a small or a large facility. Its node is shown first, to the left, because it is the decision the retailer must make now. The second decision node is reached only if a small facility is built and demand turns out to be high. Finally, the third decision point is reached only if the retailer builds a large facility and demand turns out to be low.

46 A – 46 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree $200 $223 $270 $40 $800 $20 $220 Don’t expand Expand Low demand [0.4] High demand [0.6] 2 FIGURE A.5 – Decision Tree for Retailer (in $000) Low demand [0.4] High demand [0.6] 3 Do nothing Advertise Modest response [0.3] Sizable response [0.7] Small facility Large facility 1

47 A – 47 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree $200 $223 $270 $40 $800 $20 $220 Don’t expand Expand Low demand [0.4] High demand [0.6] 2 FIGURE A.5 – Decision Tree for Retailer (in $000) Low demand [0.4] High demand [0.6] 3 Do nothing Advertise Modest response [0.3] Sizable response [0.7] Small facility Large facility x $20 = $6 0.7 x $220 = $154 $6 + $154 = $160

48 A – 48 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree $200 $223 $270 $40 $800 $20 $220 Don’t expand Expand Low demand [0.4] High demand [0.6] 2 FIGURE A.5 – Decision Tree for Retailer (in $000) Low demand [0.4] High demand [0.6] 3 Do nothing Advertise Modest response [0.3] Sizable response [0.7] Small facility Large facility 1 $160

49 A – 49 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree $200 $223 $270 $40 $800 $20 $220 Don’t expand Expand Low demand [0.4] High demand [0.6] 2 FIGURE A.5 – Decision Tree for Retailer (in $000) Low demand [0.4] High demand [0.6] 3 Do nothing Advertise Modest response [0.3] Sizable response [0.7] Small facility Large facility 1 $160 $270

50 A – 50 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree $200 $223 $270 $40 $800 $20 $220 Don’t expand Expand Low demand [0.4] High demand [0.6] 2 FIGURE A.5 – Decision Tree for Retailer (in $000) Low demand [0.4] High demand [0.6] 3 Do nothing Advertise Modest response [0.3] Sizable response [0.7] Small facility Large facility 1 $160 $270 x 0.4 = $80 x 0.6 = $162 $80 + $162 = $242

51 A – 51 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree $200 $223 $270 $40 $800 $20 $220 Don’t expand Expand Low demand [0.4] High demand [0.6] 2 FIGURE A.5 – Decision Tree for Retailer (in $000) Low demand [0.4] High demand [0.6] 3 Do nothing Advertise Modest response [0.3] Sizable response [0.7] Small facility Large facility 1 $160 $270 $242 x 0.6 = $ x $160 = $64 $544

52 A – 52 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree $200 $223 $270 $40 $800 $20 $220 Don’t expand Expand Low demand [0.4] High demand [0.6] 2 FIGURE A.5 – Decision Tree for Retailer (in $000) Low demand [0.4] High demand [0.6] 3 Do nothing Advertise Modest response [0.3] Sizable response [0.7] Small facility Large facility 1 $160 $270 $242 $544

53 A – 53 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Analyzing a Decision Tree $200 $223 $270 $40 $800 $20 $220 Don’t expand Expand Low demand [0.4] High demand [0.6] 2 FIGURE A.5 – Decision Tree for Retailer (in $000) Low demand [0.4] High demand [0.6] 3 Do nothing Advertise Modest response [0.3] Sizable response [0.7] Small facility Large facility 1 $160 $270 $242 $544

54 A – 54 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.6 a.Draw the decision tree for the Fletcher, Cooper, and Wainwright Application A.5 problem b.What is the expected payoff for the best alternative in the decision tree below? Alternative Land routes, No Treaty (0.50) Land Routes, Treaty Only (0.30) Sea routes, Only (0.20) Arrows840,000440,000190,000 Barrels370,000220,000670,000 Wagons25,0001,150,000-25,000

55 A – 55 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Application A.6

56 A – 56 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 1 A small manufacturing business has patented a new device for washing dishes and cleaning dirty kitchen sinks The owner wants reasonable assurance of success Variable costs are estimated at $7 per unit produced and sold Fixed costs are about $56,000 per year a.If the selling price is set at $25, how many units must be produced and sold to break even? Use both algebraic and graphic approaches. b.Forecasted sales for the first year are 10,000 units if the price is reduced to $15. With this pricing strategy, what would be the product’s total contribution to profits in the first year?

57 A – 57 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 1 SOLUTION a.Beginning with the algebraic approach, we get Q = Fp – cFp – c = 3,111 units = 56, – 7 Using the graphic approach, shown in Figure A.6, we first draw two lines: The two lines intersect at Q = 3,111 units, the break-even quantity Total revenue= Total cost= 25 Q 56, Q

58 A – 58 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 1 b.Total profit contribution= Total revenue – Total cost = pQ – ( F + cQ ) = 15(10,000) – [56, (10,000)] = $24,000

59 A – 59 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Total costs Break-even quantity 250 – 200 – 150 – 100 – 50 – 0 – Units (in thousands) Dollars (in thousands) |||||||| |||||||| Total revenues 3.1 $77.7 Solved Problem 1 FIGURE A.6

60 A – 60 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 2 Binford Tool Company is screening three new product idea: A, B, and C. Resource constraints allow only one of them to be commercialized. The performance criteria and ratings, on a scale of 1 (worst) to 10 (best), are shown in the following table. The Binford managers give equal weights to the performance criteria. Which is the best alternative, as indicated by the preference matrix method? Rating Performance CriteriaProduct AProduct BProduct C 1.Demand uncertainty and project risk392 2.Similarity to present products786 3.Expected return on investment (ROI) Compatibility with current manufacturing process Competitive Strategy465

61 A – 61 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 2 SOLUTION Each of the five criteria receives a weight of 1/5 or 0.20 Rating Performance CriteriaProduct AProduct BProduct C 1.Uncertainty and risk392 2.Similarity786 3.ROI Compatibility476 5.Strategy465 The best choice is product B as Products A and C are well behind in terms of total weighted score (0.20 × 3) + (0.20 × 7) + (0.20 × 10) + (0.20 × 4) + (0.20 × 4) = 5.6 (0.20 × 9) + (0.20 × 8) + (0.20 × 4) + (0.20 × 7) + (0.20 × 6) = 6.8 (0.20 × 2) + (0.20 × 6) + (0.20 × 8) + (0.20 × 6) + (0.20 × 5) = 5.4 ProductCalculationTotal Score A B C

62 A – 62 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 3 Adele Weiss manages the campus flower shop. Flowers must be ordered three days in advance from her supplier in Mexico. Although Valentine’s Day is fast approaching, sales are almost entirely last-minute, impulse purchases. Advance sales are so small that Weiss has no way to estimate the probability of low (25 dozen), medium (60 dozen), or high (130 dozen) demand for red roses on the big day. She buys roses for $15 per dozen and sells them for $40 per dozen. Construct a payoff table. Which decision is indicated by each of the following decision criteria? a. Maximin b. Maximax c. Laplace d. Minimax regret

63 A – 63 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 3 SOLUTION The payoff table for this problem is Demand for Red Roses Alternative Low (25 dozen) Medium (60 dozen) High (130 dozen) Order 25 dozen$625 Order 60 dozen$100$1,500 Order 130 dozen($950)$450$3,250 Do nothing$0

64 A – 64 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 3 a.Under the maximin criteria, Weiss should order 25 dozen, because if demand is low, Weiss’s profits are $625, the best of the worst payoffs. b.Under the maximax criteria, Weiss should order 130 dozen. The greatest possible payoff, $3,250, is associated with the largest order. c.Under the Laplace criteria, Weiss should order 60 dozen. Equally weighted payoffs for ordering 25, 60, and 130 dozen are about $625, $1,033, and $917, respectively. d.Under the minimax regret criteria, Weiss should order 130 dozen. The maximum regret of ordering 25 dozen occurs if demand is high: $3,250 – $625 = $2,625. The maximum regret of ordering 60 dozen occurs if demand is high: $3,250 – $1,500 = $1,750. The maximum regret of ordering 130 dozen occurs if demand is low: $625 – (–$950) = $1,575.

65 A – 65 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 4 White Valley Ski Resort is planning the ski lift operation for its new ski resort and wants to determine if one or two lifts will be necessary Each lift can accommodate 250 people per day and skiing occurs 7 days per week in the 14-week season and lift tickets cost $20 per customer per day The table below shows all the costs and probabilities for each alternative and condition Should the resort purchase one lift or two? AlternativesConditionsUtilizationInstallationOperation One liftBad times (0.3)0.9$50,000$200,000 Normal times (0.5)1.0$50,000$200,000 Good times (0.2)1.0$50,000$200,000 Two liftsBad times (0.3)0.9$90,000$200,000 Normal times (0.5)1.0$90,000$400,000 Good times (0.2)1.0$90,000$400,000

66 A – 66 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Solved Problem 4 SOLUTION The decision tree is shown in Figure A.7. The payoff ($000) for each alternative-event branch is shown in the following table. The total revenues from one lift operating at 100 percent capacity are $490,000 (or 250 customers × 98 days × $20/customer-day). 0.9(490) – ( ) = (490) – ( ) = (490) – ( ) = (490) – ( ) = (490) – ( ) = 441 AlternativesEconomic ConditionsPayoff Calculation (Revenue – Cost) One liftBad times Normal times Good times Two liftsBad times Normal times Good times

67 A – 67 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Bad times [0.3] Normal times [0.5] Good times [0.2] $191 $240 Bad times [0.3] Normal times [0.5] Good times [0.2] $151 $245 $441 One lift Two lifts $256.0 $225.3 $256.0 Solved Problem 4 0.3(191) + 0.5(240) + 0.2(240) = (151) + 0.5(245) + 0.2(441) = FIGURE A.7

68 A – 68 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall.


Download ppt "A – 1 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Decision Making A For Operations Management, 9e by Krajewski/Ritzman/Malhotra."

Similar presentations


Ads by Google