TABLE 16-4
The number of cases of merlot wine sold by a Paso Robles winery in an 8-year period
follows.
Referring to Table 16-4, exponentially smooth the wine sales with a weight or
smoothing constant of 0.4.
You were told that the amount of time lapsed between consecutive trades on the New
York Stock Exchange followed a normal distribution with a mean of 15 seconds. You
were also told that the probability that the time lapsed between two consecutive trades
to fall between 16 to 17 seconds was 13%. The probability that the time lapsed between
two consecutive trades would fall below 13 seconds was 7%. What is the probability
that the time lapsed between two consecutive trades will be between 14 and 17
seconds?
A high school debate team of 4 is to be chosen from a class of 35. How many possible
ways can the team be formed?
TABLE 2-9
The frequency distribution below represents the rents of 250 randomly selected
federally subsidized apartments in a small town.
Referring to Table 2-9, the relative frequency of the second class is ________.
TABLE 8-3
To become an actuary, it is necessary to pass a series of 10 exams, including the most
important one, an exam in probability and statistics. An insurance company wants to
estimate the mean score on this exam for actuarial students who have enrolled in a
special study program. They take a sample of 8 actuarial students in this program and
determine that their scores are: 2, 5, 8, 8, 7, 6, 5, and 7. This sample will be used to
calculate a 90% confidence interval for the mean score for actuarial students in the
special study program.
Referring to Table 8-3, the critical value used in constructing a 90% confidence interval
is ________.
TABLE 13-4
The managers of a brokerage firm are interested in finding out if the number of new
clients a broker brings into the firm affects the sales generated by the broker. They
sample 12 brokers and determine the number of new clients they have enrolled in the
last year and their sales amounts in thousands of dollars. These data are presented in the
table that follows.
Referring to Table 13-4, the managers of the brokerage firm wanted to test the
hypothesis that the population slope was equal to 0. The denominator of the test statistic
is . The value of in this sample is ________.
TABLE 17-11
A logistic regression model was estimated in order to predict the probability that a
randomly chosen university or college would be a private university using information
on mean total Scholastic Aptitude Test score (SAT) at the university or college, the
room and board expense measured in thousands of dollars (Room/Brd), and whether the
TOEFL criterion is at least 550 (Toefl550 = 1 if yes, 0 otherwise.) The dependent
variable, Y, is school type (Type = 1 if private and 0 otherwise).
Referring to Table 17-11, what should be the decision (‘reject’ or ‘do not reject’) on the
null hypothesis when testing whether SAT makes a significant contribution to the model
in the presence of the other independent variables at a 0.05 level of significance?
TABLE 5-7
There are two houses with almost identical characteristics available for investment in
two different neighborhoods with drastically different demographic composition. The
anticipated gain in value when the houses are sold in 10 years has the following
probability distribution:
Referring to Table 5-7, what is the expected value gain if you invest in both houses?
The amount of tea leaves in a can from a particular production line is normally
distributed with = 110 grams and = 25 grams. Approximately 83% of the can will
have at least how many grams of tea leaves?
TABLE 6-7
A company has 125 personal computers. The probability that any one of them will
require repair on a given day is 0.15.
Referring to Table 6-7 and assuming that the number of computers that requires repair
on a given day follows a binomial distribution, compute the probability that there will
be more than 25 computers that require repair on a given day using a normal
approximation.