OM375 Final Study Guide
Which type of spreadsheet cell represents the decision variables in an LP model while using Excel Solver? A. Variable cell B. Constant cell C. Constraint cell D. Target or set cell
A. Variable cell
Limited resources are modeled in optimization problems as A. constraints. B. alternatives. C. objective function. D. decision variables.
A. constraints.
The shadow price of a nonbinding constraint is A. positive B. zero C. negative D. indeterminate
B. zero
Which type of spreadsheet cell represents the left hand sides (LHS) formulas in an LP model while using Solver? A. Target or set cell B. Changing variable cell C. Constraint cell D. Constant cell
C. Constraint cell
Which of the following is most likely to be used when faced with the decision of how to arrange furniture in a room? A. Mathematical model B. Physical model C. Mental model D. Visual model
C. Mental model
If there is no way to simultaneously satisfy all the constraints in an LP model the problem is said to be A. multi-optimal. B. open ended. C. infeasible. D. unbounded.
C. infeasible.
In which step of the problem-solving process is the main focus to generate and evaluate alternatives? A. Test results B. Identify problem C. Formulate model D. Use model to analyze problem
D. Use model to analyze problem
An Excel add-in tool used for data mining is called A. XML B. Data Miner C. GS4 D. XL Miner
D. XL Miner
Binary decision variables: 1. must be integers 2. may be continuous 3. are either 0 or 1 4. may be negative
3. are either 0 or 1
What are binary integer variables? A. Variables whose sum of digits is 2. B. Variables with any two values, a and b. C. Variables with values 0 and 1. D. Variables with values between 0 and 1.
C. Variables with values 0 and 1.
A test sample is often used to perform ___________ of how well the model will work with new data A. a belief B. a guess C. an honest assessment D. an estimate
C. an honest assessment
Which of the following problem-solving steps is often considered the most difficult? A. Test results. B. Identify the problem. C. Analyze the model. D. Implement the solution.
D. Implement the solution.
Plots useful in data mining analysis can be accessed in Excel using the _______ add-in A. Charts B. Visual Basic C. Data Analysis D. XLMiner
D. XLMiner
In the ________ step of data mining, a researcher attempts to form logical groupings of data in the set A. prediction B. classification C. categorization D. association/segmentation
D. association/segmentation
Normalization of data involves A. subtracting the grand mean from each observation B. dividing each observation by total variance C. dividing each observation by average range D. expressing each variable on a common, standardized scale
D. expressing each variable on a common, standardized scale
A change in the right hand side of a constraint changes A. the slope of the objective function B. objective function coefficients C. other right hand sides D. the feasible region
D. the feasible region
Define the decision models and describe the importance of such models.
Decision Analysis - Identifying and evaluating the different possible courses of action that might be chosen to address a decision problem. A modeling approach to decision making is beneficial in that the decision maker can analyze the probable impact of numerous alternative before selecting an alternative for implementation.
Which of the following categories of modeling techniques addresses uncertainty in the values of the independent variables? A. Descriptive models B. Predictive models C. Prescriptive models D. Scale models
A. Descriptive models
Technique(s) used in association step of data mining include A. affinity analysis B. integer networks C. all of the above D. binary analysis
A. affinity analysis
Any integer variable in an ILP that assumes a fractional value in the optimal solution to the relaxed LP problem can be designated A. a splitting variable. B. a branching variable. C. a diverging variable. D. a bifurcating variable.
B. a branching variable.
Pure IP formulation requires that: A. some decision variables must be integer B. all decision variables must be integer C. the optimal objective function value must be integer D. some decision variables and the optimal value of the objective function must be integer
B. all decision variables must be integer
For maximization problems, the optimal objective function value to the LP relaxation provides what for the optimal objective function value of the ILP problem? A. An additional constraint for the ILP problem. B. A lower bound. C. An upper bound. D. An alternative optimal solution.
C. An upper bound.
The Cell Value column in the Solver Answer Report shows A. which constraints are binding. B. final (optimal) value assumed by each constraint cell. C. objective function values. D. Right hand sides of constraints.
B. final (optimal) value assumed by each constraint cell.
Which type of spreadsheet cell represents the objective function in an LP model while using Excel Solver? A. Constraint cell B. Changing variable cell C. Objective cell D. Constant cell
C. Objective cell
A mathematical programming application employed by a shipping company is most likely A. a financial planning problem. B. a product mix problem. C. a manufacturing problem. D. a routing and logistics problem.
D. a routing and logistics problem.
Technique(s) used in classification step of data mining include A. logistic regression B. all of the above C. discriminant analysis D. neural networks
B. all of the above
Benefits of sensitivity analysis include all the following except: A. provides a better picture of how solutions change as model factors change. B. fosters managerial acceptance of the optimal solution. C. overcomes management skepticism of optimal solutions. D. answers potential managerial questions regarding the solution to an LP problem.
B. fosters managerial acceptance of the optimal solution.
Describe Binary Integer Variables in 2-3 sentences.
Binary Integer Variables can either be 0 or 1. 0 represents absence and 1 represents presence. Some examples include yes/no, on/off, etc.Binary variables are a subset of integer variables. Binary variables can be used to model a number of logical conditions that might apply in a variety of problems. For example, in the CRT Technologies problem, several of the projects under consideration (e.g., projects 1, 3, and 6) might represent alternative approaches for producing a certain part for a product.
The essence of decision analysis is: A. finding the root cause of why something has gone wrong. B. breaking down complex situations into manageable elements. C. thinking ahead to avoid negative consequences. D. choosing the best course of action among alternatives.
D. choosing the best course of action among alternatives.
Why would someone wish to use a spreadsheet model? A. All of these. B. Because spreadsheets are convenient. C. To analyze decision alternatives. D. To implement a computer model.
A. All of these.
When performing sensitivity analysis, which of the following assumptions must apply? A. All other coefficients remain constant. B. Only right hand side changes really mean anything. C. The X1 variable change is the most important. D. The non-negativity assumption can be relaxed
A. All other coefficients remain constant.
Which of the following statements is true of using models in problem solving and decision analysis? A. It is something everyone has done before. B. It is tied to the use of computers. C. It is a fairly new idea. D. It is required in order to find good solutions.
A. It is something everyone has done before.
What most motivates a business to be concerned with efficient use of their resources? A. Resources are limited and valuable. B. Efficient resource use increases business costs. C. Inefficient resource use means hiring more workers. D. Efficient resources use means more free time.
A. Resources are limited and valuable.
Which of the following is not true regarding discriminant analysis? A. The classification rule selected perfectly classifies the data used to derive the classification rule. B. The confusion matrix summarizes classification results. C. Discriminant analysis is based on discrete or categorical dependent variables. C. The classification rule translates discriminant scores into group membership.
A. The classification rule selected perfectly classifies the data used to derive the classification rule.
Which of the following statements is false concerning either of the Allowable Increase and Allowable Decrease columns in the Sensitivity Report? A. The values equate the decision variable profit to the cost of resources expended. B. The values give the range over which a shadow price is accurate. C. The values give the range over which an objective function coefficient can change without changing the optimal solution. D. The values provide a means to recognize when alternate optimal solution exist.
A. The values equate the decision variable profit to the cost of resources expended.
Which of the following is not a benefit of using binary variables? A. With only 2 values, Solver can work faster. B. Binary variables can replace some IF() conditions. C. Binary variables are useful in selection problems. D. Binary variables can enforce logical conditions.
A. With only 2 values, Solver can work faster.
A variable with a final value equal to its simple lower or upper bound and a reduced cost of zero indicates that A. an alternate optimal solution exists. B. an error in formulation has been made. C. the right hand sides should be increased. D. the objective function needs new coefficients.
A. an alternate optimal solution exists.
What are the three common elements of an optimization problem? A. decisions, constraints, an objective. B. decisions, resource requirements, a profit function. C. objectives, resources, goals. D. decision variables, profit levels, costs.
A. decisions, constraints, an objective.
A manager should consider how sensitive the model is to changes in all of the following except A. differential coefficients. B. objective function coefficients. C. constraint coefficients. D. right-hand side values for constraints.
A. differential coefficients.
The ultimate goal of the problem identification step of the problem-solving process is A. identifying the root problem or problems causing the mess. B. convincing the decision maker the mess is really a problem that can be solved. C. helping the decision maker realize there is a problem. D. collecting lots of information.
A. identifying the root problem or problems causing the mess.
Beneficial uses of the testing process include all of the following except: A. improving solutions after the implementation step. B. finding that some important assumption has been left out of the model. C. double checking the validity the model. D. giving no new insights into the nature of the problem.
A. improving solutions after the implementation step.
A correlation coefficient A. measures the strength of a linear association between two variables B. measures the strength of logical association between two variables C. measures the strength of statistical association between two variables D. measures the strength of physical association between two variables
A. measures the strength of a linear association between two variables
A binding less than or equal to (≤) constraint in a maximization problem means A. that all of the resource represented by the constraint is consumed in the solution. B. it is not a constraint that the level curve contacts. C. another constraint is limiting the solution. D. the requirement for the constraint has been exceeded.
A. that all of the resource represented by the constraint is consumed in the solution.
Binary variables are useful for modeling A. the fixed-charge problem B. the shortest route problem C. the transportation problem D. the assignment problem
A. the fixed-charge problem
The goal of discriminant analysis is A. to develop a rule for predicting to what group a new observation is most likely to belong. B. to develop a model to predict new dependent values. C. none of these. C. to develop a rule for predicting how independent variable values predict dependent values.
A. to develop a rule for predicting to what group a new observation is most likely to belong.
Binding constraints have A. zero slack. B. negative slack. C. positive slack. D. surplus resources.
A. zero slack.
Which of the following fields of study is defined in Chapter One as the one that "uses computers, statistics, and mathematics to solve business problems"? A. Accounting B. Business analytics C. Scientific management D. Information systems
B. Business analytics
Why do we study the graphical method of solving LP problems? A. It provides better solutions than computerized methods. B. To develop an understanding of the linear programming strategy. C. Lines are easy to draw on paper. D. It is faster than computerized methods.
B. To develop an understanding of the linear programming strategy.
The LP relaxation of an ILP problem A. will not contain the feasible integer solutions to the original ILP problem. B. always encompasses all the feasible integer solutions to the original ILP problem. C. encompasses different set of feasible integer solutions to the original ILP problem. D. encompasses at least 90% of the feasbile integer solutions to the original ILP problem.
B. always encompasses all the feasible integer solutions to the original ILP problem.
How is an LP problem changed into an ILP problem? A. by adding constraints that the decision variables be non-negative. B. by adding integrality conditions. C. by adding discontinuity constraints. D. by making the RHS values integer.
B. by adding integrality conditions.
In the ________ step of data mining, a researcher attempts to estimate to which discrete group an observation belongs to A. prediction B. classification C. association/segmentation D. categorization
B. classification
An integrality condition indicates that some (or all) of the A. RHS values for constraints must be integer B. decision variables must be integer C. constraint coefficients must be integer D. objective function coefficients must be integer
B. decision variables must be integer
In classification techniques the dependent variable is A. bounded from below B. discrete C. bounded from above D. continuous
B. discrete
For an infeasible problem, the feasible region: A. has only one optimal solution B. is an empty set C. is unbounded D. has infinite number of feasible solutions
B. is an empty set
The coefficients in an LP model (cj, aij, bj) represent A. random variables. B. numeric constants. C. random constants. D. numeric variables.
B. numeric constants.
The allowable increase for a changing cell (decision variable) is A. how many more units to produce to maximize profits. B. the amount by which the objective function coefficient can increase without changing the optimal solution. C. how much to charge to get the optimal solution. D. the amount by which constraint coefficient can increase without changing the optimal solution.
B. the amount by which the objective function coefficient can increase without changing the optimal solution.
The allowable decrease for a constraint is A. how many more units of resource to purchase to maximize profits. B. the amount by which the resource can decrease given shadow price. C. how much resource to use to get the optimal solution. D. the amount by which constraint coefficient can increase without changing the final optimal value.
B. the amount by which the resource can decrease given shadow price.
When the objective function can increase without ever contacting a constraint the LP model is said to be A. infeasible. B. unbounded. C. multi-optimal. D. open ended.
B. unbounded.
A way to detecting and avoiding overfitting is to A. use rigorous statistical tools B. use the validation sample to calibrate the model C. use computer simulation D. use repeated runs of the model and averaging the results
B. use the validation sample to calibrate the model
The difference between the right-hand side (RHS) values of the constraints and the final (optimal) value assumed by the left-hand side (LHS) formula for each constraint is called the slack and is found in the A. Status report B. Slack report C. Answer report D. Cell Value report
C. Answer report
What is the goal in optimization? A. Find the values of the decision variables that satisfy all constraints. B. Find the values of the decision variables that use all available resources. C. Find the decision variable values that result in the best objective function and satisfy all constraints. D. None of these.
C. Find the decision variable values that result in the best objective function and satisfy all constraints.
One approach to solving integer programming problems is to ignore the integrality conditions and solve the problem with continuous decision variables. This is referred to as A. LP approximation. B. quickest solution method. C. LP relaxation. D. LP satisficing.
C. LP relaxation.
Which of the following fields of business analytics finds the optimal method of using resources to achieve the objectives of a business? A. Regression B. Simulation C. Mathematical programming D. Discriminant analysis
C. Mathematical programming
All of the following are benefits of modeling except: A. Modeling is helpful in examining things that would be impossible to do in reality. B. Modeling delivers needed information on a more timely basis. C. Modeling finds the right answers to incorrect or flawed problem statements. D. Modeling is less expensive than implementing several alternative solutions.
C. Modeling finds the right answers to incorrect or flawed problem statements.
When do alternate optimal solutions occur in LP models? A. Alternate optimal solutions indicate an infeasible condition. B. When a non-binding constraint is perpendicular to a level curve. C. When a binding constraint is parallel to a level curve. D. When a constraint is parallel to another constraint.
C. When a binding constraint is parallel to a level curve.
In a decision-making problem, anchoring effects occur when A. a person in a position of authority exerts his or her opinion very forcefully. B. decision makers are tied too closely to previous decisions. C. a seemingly trivial factor serves as a starting point for estimations. D. organizations refuse to consider new alternatives.
C. a seemingly trivial factor serves as a starting point for estimations.
When a manager considers the effect of changes in an LP model's coefficients he/she is performing A. a random analysis. B. a coefficient analysis. C. a sensitivity analysis. D. a qualitative analysis.
C. a sensitivity analysis.
In preparation for mining an analyst should A. explore the relationships between variables B. verify completeness and accuracy of the data C. all of the above D. clean the data addressing missing values, errors, etc.
C. all of the above
Technique(s) used in prediction step of data mining include A. the k'th largest neighbor technique B. neural networks C. all of the above D. regression analysis
C. all of the above
Variables, which are not required to assume strictly integer values are referred to as A. infinite. B. strictly non-integer. C. continuous. D. discrete.
C. continuous.
Oversampling forces a classification method to A. classifying records correctly B. classifying records incorrectly C. discriminate between groups D. perform a large number of iterations
C. discriminate between groups
The setup cost incurred in preparing a machine to produce a batch of product is an example of a A. variable cost. B. random charge. C. fixed charge. D. sunk cost.
C. fixed charge.
Linear programming problems have A. non-linear objective functions, non-linear constraints. B. non-linear objective functions, linear constraints. C. linear objective functions, linear constraints. D. linear objective functions, non-linear constraints.
C. linear objective functions, linear constraints.
A change in the right hand side of a binding constraint may change all of the following except A. optimal value of the decision variables B. slack values C. other right hand sides D. objective function value
C. other right hand sides
The categories of modeling techniques presented in this book include all of the following except: A. prescriptive models. B. predictive models. C. preventive models. D. descriptive models.
C. preventive models.
Suppose that two variables are found to be significantly correlated. A researcher may A. replace the two variables by their squared difference B. replace the two variables by their product C. remove one variable from the data set D. remove both variables from the data set
C. remove one variable from the data set
One element in cleaning the data set in the mining process involves A. adding more variables to the data set B. calculating the coefficient of multiple correlation C. removing unimportant variables D. calculating the adjusted R2
C. removing unimportant variables
Consistently using a structured, model based process to make decisions A. is evidence that luck plays an important role in decision making. B. always leads to well-deserved success in managerial decision making. C. should produce good outcomes more frequently. D. is less effective than making decisions in a haphazard manner.
C. should produce good outcomes more frequently.
The allowable decrease for a changing cell (decision variable) is A. the amount by which the constraint coefficient can decrease without changing final optimal solution. B. an indication of how many more units to produce to maximize profits. C. the amount by which objective function coefficient can decrease without changing the final optimal solution. D. an indication of how much to charge to get the optimal solution.
C. the amount by which objective function coefficient can decrease without changing the final optimal solution.
The reduced cost for a changing cell (decision variable) is A. the amount by which the objective function value changes if the variable is increased by one unit. B. how many more units to product to maximize profits. C. the per unit profits minus the per unit costs for that variable. D. equal to zero for variables at their optimal values.
C. the per unit profits minus the per unit costs for that variable.
A manufacturing company has costs associated with production preparation and with per unit production. The per unit production costs are referred to as A. marginal costs. B. production cost constraint coefficients. C. variable costs. D. decision variables.
C. variable costs.
Steps in the data mining process include the following (in sequence) A. (identify opportunity), (collect data), (identify tasks and tools, (partition data), (build and evaluate models), (deploy models) B. (identify opportunity), (collect data), (explore, understand and prepare data), (identify tasks and tools, (build and evaluate models), (deploy models) C. (collect data), (explore, understand and prepare data), (identify tasks and tools, (partition data), (build and evaluate models), (deploy models) D. (identify opportunity), (collect data), (explore, understand and prepare data), (identify tasks and tools, (partition data), (build and evaluate models), (deploy models)
D. (identify opportunity), (collect data), (explore, understand and prepare data), (identify tasks and tools, (partition data), (build and evaluate models), (deploy models)
For minimization problems, the optimal objective function value to the LP relaxation provides what for the optimal objective function value of the ILP problem? A. An additional constraint for the ILP problem. B. An alternative optimal solution. C. An upper bound. D. A lower bound.
D. A lower bound.
Which of the following special conditions in an LP model represent potential errors in the mathematical formulation? A. Alternate optimum solutions and redundant constraints B. Alternate optimum solutions and infeasibility C. Redundant constraints and unbounded solutions D. Infeasibility and unbounded solutions
D. Infeasibility and unbounded solutions
In which of the following categories of modeling techniques are the specifications of the relationships between dependent and independent variables unknown or ill-defined? A. Open models B. Prescriptive models C. Predictive models D. Descriptive models
D. Predictive models
A company wants to select 1 project from a set of 4 possible projects. Which of the following constraints ensures that only 1 will be selected? A. X1 + X2 + X3 + X4 ≥ 1 B. X1 + X2 + X3 + X4 ≥ 0 C. X1 + X2 + X3 + X4 ≤ 1 D. X1 + X2 + X3 + X4 = 1
D. X1 + X2 + X3 + X4 = 1
A company wants to select no more than 2 projects from a set of 4 possible projects. Which of the following constraints ensures that no more than 2 will be selected? A. X1 + X2 + X3 + X4 ≥ 2 B. X1 + X2 + X3 + X4 ≥ 0 C. X1 + X2 + X3 + X4 = 2 D. X1 + X2 + X3 + X4 ≤ 2
D. X1 + X2 + X3 + X4 ≤ 2
The sensitivity analysis provides information about which of the following? A. the impact of a change to an objective function coefficient. B. the impact of a change in a resource level. C. the impact of adding simple upper or lower bounds on a decision variable. D. all of these.
D. all of these.
A set of values for the decision variables that satisfy all the constraints and yields the best objective function value is A. a feasible solution. B. both (a) and (c). C. a corner point solution. D. an optimal solution.
D. an optimal solution.
The objective function value for the ILP problem can never A. be as poor as the optimal solution to its LP relaxation. B. be worse than the optimal solution to its LP relaxation. C. be as good as the optimal solution to its LP relaxation. D. be better than the optimal solution to its LP relaxation.
D. be better than the optimal solution to its LP relaxation.
Suppose you want to minimize an objective function z=2x1+3x2. Both decision variables must be integer. The optimal solution to the LP relaxation will: A. will be within 5% of the optimal IP solution value B. be larger than the optimal IP solution C. can be either smaller or larger than the optimal IP solution D. be smaller than the optimal IP solution
D. be smaller than the optimal IP solution
The slope of the level curve for the objective function value can be changed by A. increasing the value of the decision variables. B. doubling all the coefficients in the objective function. C. increasing the right hand sides of constraints. D. changing a coefficient in the objective function.
D. changing a coefficient in the objective function.
If constraints are added to an LP model the feasible solution space will generally A. remain the same. B. increase. C. become more feasible. D. decrease.
D. decrease.
The constraints of an LP model define the A. practical region B. opportunity region C. maximal region D. feasible region
D. feasible region
There are a variety of problems a manager might face. While presenting and defending your approach, how would you complete this thought? Several different modeling techniques are available to solve managerial decision problems, A. most problems faced by managers are fundamentally the same. B. the wrong choice of modeling technique is a common source of implementation difficulties. C. students should develop a strong preference and expertise in one technique so when faced with problems as managers they can formulate them as a model that can be solved by their favorite technique. D. fundamental characteristics of the problem guide the selection of an appropriate modeling technique.
D. fundamental characteristics of the problem guide the selection of an appropriate modeling technique.
The goal of the modeling approach to problem solving is to A. determine a set of optimal decisions. B. ensure optimality of decisions. C. determine feasibility of decisions. D. help individuals make good decisions.
D. help individuals make good decisions.
Virtually everyone who uses a spreadsheet today for model building and decision making A. possesses an advanced knowledge of mathematics and computer programming languages. B. is a CPA. C. is in a position to influence decision makers. D. is a practitioner of business analytics.
D. is a practitioner of business analytics.
Overfitting refers to A. fitting the model too loosely B. fitting the model too tightly C. underestimating model parameters D. placing too much emphasis on the sample-specific noise
D. placing too much emphasis on the sample-specific noise
A redundant constraint is one which A. can only increase the objective function value. B. is parallel to the level curve. C. is added after the problem is already formulated. D. plays no role in determining the feasible region of the problem.
D. plays no role in determining the feasible region of the problem.
To be effective, a modeler must A. collect the proper input data for the model. B. be an effective presenter of results. C. apply the correct modeling technique. D. understand how modeling fits into the problem-solving process.
D. understand how modeling fits into the problem-solving process.
