PANCAKES Flashcards
Objectives in multi-criteria problems seldom conflict.
FALSE
Target values will never be met precisely in a goal programming problem.
FALSE
Goal equations consist of a function that defines goal achievement and deviation variables that measure the distance from the target.
TRUE
There can only be one goal at each priority level.
FALSE
To solve a goal programming problem with preemptive priorities, successive linear programming problems, with an adjustment to the objective function and an additional constraint, must be solved.
TRUE
If a problem has multiple goals at different priority levels, then usually they can all be achieved.
FALSE
For a scoring model, the decision maker evaluates each decision alternative using equally weighted criteria.
FALSE
If airline A is moderately preferred to airline B, at a value of 3, then airline B is compared to airline A at a value of -3.
FALSE
An item’s priority reveals how it compares to its competitors on a specific criterion.
TRUE
The priority matrix shows the priority for each item on each criterion.
TRUE
One limitation of a scoring model is that it uses arbitrary weights that do not necessarily reflect the preferences of the individual decision maker.
FALSE
A consistency ratio greater than 0.10 indicates inconsistency in the pair-wise comparisons.
TRUE
Calculating the priority of each criterion in terms of its contribution to the overall goal is known as developing the hierarchy.
FALSE
The goal programming approach can be used when an analyst is confronted with an infeasible solution to an ordinary linear problem.
TRUE
A problem involving only one priority level is not considered a goal programming problem.
FALSE
A decision with more than one objective
a. cannot have an optimal solution
b. requires the decision maker to place the objectives in some order of importance
c. depends on the probability of satisfying each objective
d. should be decomposed into a separate model for each objective
Requires the decision maker to place the objectives in some order of importance
Variables that indicate the distance a target is from the level achieved are called ___________
Deviation variables
Preemptive priorities in goal programming
a. show the target values for the problem
b. prevent sacrifice of a goal to satisfy a lower level one
c. force the problem to be a standard linear program
d. limit deviations to d- only
Prevent sacrifice of a goal to satisfy a lower level one
Deviation variables that occur in the objective function indicate
a. the targets
b. the priorities
c. only the areas that are of concern
d. the difference between all actual and target values
Only the areas that are of concern
The variable d- measures
The amount under the target and is similar to a slack
The constraint 5x1+3x2 <= 150 is modified to become a goal equation, and priority one is to avoid overutilization. Which of the following is appropriate?
Min P1d1; 5x1 + 3x2 + d1- - d1+ = 150
The goal programming problem with the objective function min P1(d1+) + P2(d2-) is initially solved by the computer and the objective function value is 0. What constraint should be added for the second problem?
d1+ = 0
A required step in the analytic hierarchy process is to determine
a. the goals to be satisfied
b. the expected value of the criteria
c. the relative importance of a set of features based on a criterion
d. how many hierarchies to use
The relative importance of a set of features based on criterion
Pair-wise comparisons are used to
a. compare criteria in terms of the overall goal
b. compare choices on each criterion
c. both a and b are true
a. Compare criteria in terms of the overall goal
b. Compare choices on each criterion
The overall priorities for decision alternatives
a. are the sum of the products of the criterion priority times the priority of the decision alternative with respect to that criterion
b. sum to 1
c. indicate what choice is preferred, but do not force that choice to be made
d. each of the above is true
a. Are the sum of the products of the criterion priority times the priority of the decision alternative with respect to that criterion
b. Sum to 1
c. Indicate what choice is preferred, but do not force that choice to be made
The steps of the scoring model include all of the following EXCEPT:
a. list the decision-making criteria and assign a weight to each
b. develop a pair-wise comparison matrix for each criterion
c. rate how well each decision alternative satisfies each criterion
d. compute the total score for each decision alternative
Develop a pair-wise compairsion matrix for each criterion
Goal programming with preemptive priorities never permits trade-offs between
Goals with different priority levels
Inconsistency in the pair-wise judgments is indicated by a consistency ratio that is
Greater than 0.10
When using a linear programming approach to solving a goal programming problem, a linear program must be solved for each
Priority level
Computing the consistency ratio for a criterion’s pair-wise comparison matrix is the next step after
Developing the criterion’s priority vector
Time series methods
a. discover a pattern in historical data and project it into the future
b. include cause-effect relationships
c. are useful when historical information is not available
a. Discover a pattern in historical data and project it into the future
b. Include cause-effect relationships
c. Are useful when historical information is not available
Gradual shifting of a time series over a long period of time is called
TREND
Seasonal components
a. cannot be predicted
b. are regular repeated patterns
c. are long runs of observations above or below the trend line
d. reflect a shift in the series over time
Are regular repeated patterns
Short-term, unanticipated, and nonrecurring factors in a time series provide the random variability known as
The irregular component
The focus of smoothing methods is to smooth
The irregular component
Forecast errors
are the differences between actual and forecast values
To select a value for a for exponential smoothing
a. use a small a when the series varies substantially
b. use a large a when the series has little random variability
c. use any value between 0 and 1
a. Use a small a when the series varies substantially
b. Use a large a when the series has little random variability
c. Use any value between 0 and 1
Linear trend is calculated as Tt = 28.5 + .75t. The trend projection for period 15 is
39.75
The multiplicative model
a. uses centered moving averages to smooth the trend fluctuations
b. removes trend before isolating the seasonal components
c. deseasonalizes a time series by dividing the values by the appropriate seasonal index
d. provides a unique seasonal index for each observation of the time series
Deseasonalizes a time seris by dividing the values by the appropriate seasonal index
Causal models
a. should avoid the use of regression analysis
b. attempt to explain a time series’ behavior
c. do not use time series data
`Attempt to explain a time series’ behavior.
A qualitative forecasting method that obtains forecasts through “group consensus” is known as the __________
Delphi approach
The forecasting method that is appropriate when the time series has no significant trend, cyclical, or seasonal effect is ___________
Moving averages
If data for a time series analysis is collected on an annual basis only, which component may be ignored?
Seasonal
One measure of the accuracy of a forecasting model is the ________
Mean absolute deviation
Which of the following is a qualitative forecasting method?
Delphi method
Which of the following forecasting methods puts the least weight on the most recent time series value?
a. exponential smooting with a =.3
b. exponential smoothing with a =.2
c. moving average using the most recent 4 periods
d. moving average using the most recent 3 periods
Exponential smoothing with a =.2
Using exponential smoothing, the demand forecast for time period 10 equals the demand forecast for time period 9 plus
a times (the error in the demand forecast for time period 9)
Time series methods base forecasts only on past values of the variables.
TRUE
Quantitative forecasting methods do not require that patterns from the past will necessarily continue in the future.
FALSE
Trend in a time series must be linear.
FALSE
All quarterly time series contain seasonality
FALSE
A four-period moving average forecast for period 10 would be found by averaging the values of periods 10, 9, 8, and 7.
FALSE
If the random variability in a time series is great, a high a value should be used to exponentially smooth out the fluctuations
FALSE
Seasonal components with values over 1.00 indicate actual values below the trend line
FALSE
To make period-to-period comparisons more meaningful and identify trend, the time series should be deseasonalized
TRUE
With fewer periods in a moving average, it will take longer to adjust to a new level of demand.
FALSE
Qualitative forecasting techniques should be applied in situations where time series data exists, but where conditions are expected to change
TRUE
For a multiplicative time series model, the sum of seasonal indexes should equal the number of seasons
TRUE
A time series model with a seasonal component will always involve quarterly data
FALSE
Any recurring sequence of points above and below the trend line lasting less than one year can be attributed to the cyclical component of the time series.
FALSE
Smoothing methods are more appropriate for a stable time series than when significant trend and/or seasonal variation are present.
TRUE
The exponential smoothing forecast for any period is the weighted average of all the previous actual values for the time series.
TRUE
The mean squared error is influenced much more by large forecast errors than by small ones.
TRUE
The mean squared error is influenced much more by large forecast errors than by small ones.
TRUE
The options from which a decision makers chooses a course of action are:
a. called the decision alternatives
b. under the control of the decision maker
c. not the same as the states of nature
a. called the decision alternatives
b. under the control of the decision maker
c. not the same as the states of nature
This describes uncontrollable natural events such as floods or freezing temperatures.
STATES OF NATURE
Exists for each pair of decision alternative and state of nature
PAYOFF
Making a good decision:
a. requires probabilities for all states of nature
b. requires a clear understanding of decision alternatives, states of nature, and payoffs
c. implies that a desirable outcome will occur
REQUIRES A CLEAR UNDERSTANDING OF DECISION ALTERNATIVES, STATES OF NATURE, AND PAYOFFS
This arranges decision alternatives and states of nature in their natural chronological order
DECISION TREE
What method for decision making without probabilities best protects the decision maker from undesirable results?
CONSERVATIVE APPROACH
Sensitivity analysis considers:
CHANGES IN THE VALUE OF THE PAYOFFS
To find the EVSI:
Use prior and sample information probabilities to calculate revised probabilities
If P(high)=.3, P(low)=.7, P(favorable/high)=.9 and P(unfavorable/low) = .6, then P(favorable) =
.55
The efficiency of sample information is:
EVSI/EVPI * (100%)
Decision tree probabilities refer to:
The probability of an uncertain event occurring
For a maximization problem, the conservative approach is often referred to as the:
MAXIMIN APPROACH
Sample information with an efficiency rating of 100% is perfect information.
TRUE
States of nature should be defined so that one and only one will actually occur.
TRUE
Decision alternatives are structured so that several could occur simultaneously.
FALSE
Square nodes in a decision treee indicate that a decision must be made.
TRUE
Circular nodes in a decision tree indicate that it would be incorrect to choose a path from the node.
TRUE
Risk analysis helps the decision maker recognize the difference between the expected value of a decision alternative and the payoff that may actually occur.
TRUE
The expected value of an alternative can never be negative.
FALSE
Expected value is the sum of the weighted payoff posibilities at a circular node in a decision tree.
TRUE
EVPI >= EVSI
TRUE
After all probabilities and payoffs are placed on a decision tree, the decision maker calculates expected values at state of nature nodes and makes selections at decision nodes.
TRUE
A decision strategy is a sequence of decisions and chance outcomes, where the decisions chosen depend on the yet to be determined outcomes of chance events.
TRUE
EVPI equals the expected regret associated with the minimax decision
TRUE
PERT and CPM
Have been combined to develop a procedure that uses the best of each
Which is not a significant challenge of project scheduling?
a. deadlines exist
b. activities are independent
c. many employees could be required
d. delays are costly
ACTIVITIES ARE INDEPENDENT
Arcs in a project network indicate:
PRECEDENCE RELATIONSHIPS
The critical
