UGBA 104 CORE EXAMINATION REVIEW
QUESTIONS AND ANSWERS SURE A+
✔✔Flaw of Averages - ✔✔mean of a function of random variables does not equal the
function of the means of the random variables
✔✔Two Exceptions to the Flaw of Averages - ✔✔(1) linear function of random variables
[e.g. mean of 5x + 3y = 5(mean of x) + 3(mean of y)]
(2) product of 2 independent random variables
[x, y are independent; mean of (x*y) = mean of x*mean of y]
✔✔Sales - ✔✔minimum of supply/demand
✔✔Unsatisfied Demand - ✔✔demand - sales
✔✔Ending Inventory - ✔✔supply - sales
✔✔ROUND(cell, digits) - ✔✔cell = cell with number to be rounded
digits = # of digits you want to round to
✔✔Psi - ✔✔polymorphic spreadsheet interpreter
✔✔RNG Cell - ✔✔cell whose value is uncertain, random, or determined by nature
✔✔Decision Cell - ✔✔cell whose value is controlled by the decision maker
✔✔Output Cell - ✔✔cell that contains some value of interest
✔✔PsiTarget(A1,X) - ✔✔generates simulation's estimate of the probability that the cell
(A1) <= X
, ✔✔T/F: When a simulation ends, the displayed value of the output cell IS the mean. -
✔✔F: no special importance, value of Output Cell for last simulation
✔✔PsiSimParam - ✔✔allows you to simulate different Decision values
✔✔Simulation - ✔✔an experiment to understand how something in reality works by
imitating its behavior in an artificial environment that mimics reality
✔✔Random Variable X - ✔✔value about which we are uncertain
✔✔Discrete Random Variable X - ✔✔takes on finite (infinitely countable) number of
values
✔✔How are Discrete Random Variables represented? - ✔✔probability mass function,
p(x)
✔✔Continuous Random Variable X - ✔✔takes on infinite number of values
✔✔How are Continuous Random Variables represented? - ✔✔probability density
function
✔✔Types of Discrete Random Variables - ✔✔(1) integer uniform
(2) custom discrete
(3) bernoulli
(4) binomial
✔✔Integer Uniform RV - ✔✔each value in a range of integers is equally likely to occur
✔✔Integer Uniform RV - Parameters - ✔✔minimum, maximum (lower, upper bound)
✔✔Integer Uniform RV - Mean - ✔✔(lower + upper)/2
✔✔Custom Discrete RV - ✔✔customized set of variables and corresponding
probabilities
✔✔Custom Discrete RV - Parameters - ✔✔(1) set of values
(2) set of corresponding probabilities
✔✔Custom Discrete RV - Mean - ✔✔weighted average of values
✔✔Bernoulli RV - ✔✔an event with two outcomes
(1) 1 with probability p
(2) 0 with probability 1-p
QUESTIONS AND ANSWERS SURE A+
✔✔Flaw of Averages - ✔✔mean of a function of random variables does not equal the
function of the means of the random variables
✔✔Two Exceptions to the Flaw of Averages - ✔✔(1) linear function of random variables
[e.g. mean of 5x + 3y = 5(mean of x) + 3(mean of y)]
(2) product of 2 independent random variables
[x, y are independent; mean of (x*y) = mean of x*mean of y]
✔✔Sales - ✔✔minimum of supply/demand
✔✔Unsatisfied Demand - ✔✔demand - sales
✔✔Ending Inventory - ✔✔supply - sales
✔✔ROUND(cell, digits) - ✔✔cell = cell with number to be rounded
digits = # of digits you want to round to
✔✔Psi - ✔✔polymorphic spreadsheet interpreter
✔✔RNG Cell - ✔✔cell whose value is uncertain, random, or determined by nature
✔✔Decision Cell - ✔✔cell whose value is controlled by the decision maker
✔✔Output Cell - ✔✔cell that contains some value of interest
✔✔PsiTarget(A1,X) - ✔✔generates simulation's estimate of the probability that the cell
(A1) <= X
, ✔✔T/F: When a simulation ends, the displayed value of the output cell IS the mean. -
✔✔F: no special importance, value of Output Cell for last simulation
✔✔PsiSimParam - ✔✔allows you to simulate different Decision values
✔✔Simulation - ✔✔an experiment to understand how something in reality works by
imitating its behavior in an artificial environment that mimics reality
✔✔Random Variable X - ✔✔value about which we are uncertain
✔✔Discrete Random Variable X - ✔✔takes on finite (infinitely countable) number of
values
✔✔How are Discrete Random Variables represented? - ✔✔probability mass function,
p(x)
✔✔Continuous Random Variable X - ✔✔takes on infinite number of values
✔✔How are Continuous Random Variables represented? - ✔✔probability density
function
✔✔Types of Discrete Random Variables - ✔✔(1) integer uniform
(2) custom discrete
(3) bernoulli
(4) binomial
✔✔Integer Uniform RV - ✔✔each value in a range of integers is equally likely to occur
✔✔Integer Uniform RV - Parameters - ✔✔minimum, maximum (lower, upper bound)
✔✔Integer Uniform RV - Mean - ✔✔(lower + upper)/2
✔✔Custom Discrete RV - ✔✔customized set of variables and corresponding
probabilities
✔✔Custom Discrete RV - Parameters - ✔✔(1) set of values
(2) set of corresponding probabilities
✔✔Custom Discrete RV - Mean - ✔✔weighted average of values
✔✔Bernoulli RV - ✔✔an event with two outcomes
(1) 1 with probability p
(2) 0 with probability 1-p
