Which of the following is NOT one of the six steps in the hypothesis testing procedure?
A. Formulate a decision rule
B. State the null and alternate hypotheses
C. Select a level for β
D. Identify the test statistic
Bones Brothers & Associates prepare individual tax returns. Over prior years, Bones
Brothers has maintained careful records regarding the time to prepare a return. The
mean time to prepare a return is 90 minutes and the standard deviation of this
distribution is 14 minutes. Suppose 100 returns from this year are selected and analyzed
regarding the preparation time. What is the probability that the mean time for the
sample of 100 returns for this year is greater than 92?
A. Approximately zero
B. 0.0832
C. 0.4168
D. 0.0764
The median of a sample will always equal the:
A. mode.
B. mean.
C. 50th percentile.
D. All of these are correct.
The length of a bridge, measured in meters, is an example of:
A. Categorical data
B. Either categorical or quantitative data
C. Measurement data
D. Quantitative data
For a relative frequency distribution, relative frequency is computed as
_____________.
A. The class width divided by the class interval
B. The class midpoint divided by the class frequency
C. The class frequency divided by the class interval
D. The class frequency divided by the total frequency
A sales representative calls on four hospitals in Westchester County. It is immaterial
what order he calls on them. How many ways can he organize his calls?
A. 4
B. 24
C. 120
D. 37
What can we conclude if the global test of regression does not reject the null
hypothesis?
A. A strong relationship exists among the variables.
B. No relationship exists between the dependent variable and any of the independent
variables.
C. The independent variables are good predictors.
D. Good forecasts are possible.
Data for fuel oil and gasoline purchased at wholesale prices for 2006 and 2010 are
shown next.
What is the Laspeyres price index?
A. 116.45
B. 116.71
C. 116.67
D. 131.56
A manager at a local bank analyzed the relationship between monthly salary and three
independent variables: length of service (measured in months), gender (0 = female, 1 =
male) and job type (0 = clerical, 1 = technical). The following ANOVA summarizes the
regression results:
In the regression model, which of the following are dummy variables?
A. Intercept
B. Service
C. Service and gender
D. Gender and job
To test the hypothesis that 55% of those families who plan to purchase a vacation
residence in Florida want a condominium, the null hypothesis is π = 0.55 and the
alternate is π ≠.55. A random sample of 400 families who planned to buy a vacation
residence revealed that 228 families want a condominium. What decision should be
made regarding the null hypothesis using the 0.01 level of significance?
A. Do not reject it.
B. Reject it.
C. Cannot accept it or reject it based on the information given.
D. Purchase a condominium.
Which of the following statements about in-control and out-of-control processes are
TRUE?
I. The mean chart and range chart always show that processes are in control.
II. A mean chart can be in control, while a range chart can be out of control.
III. A mean chart can be out of control, while a range chart can be in control.
A. I only
B. II only
C. II and III
D. I and III
A sample of single persons receiving Social Security payments revealed these monthly
benefits: $826, $699, $1,087, $880, $839, and $965. How many observations are below
the median?
A. 1
B. 2
C. 3
D. 3.5
The time to fly between New York City and Chicago is uniformly distributed with a
minimum of 120 minutes and a maximum of 150 minutes. What is the distribution’s
mean?
A. 120 minutes
B. 150 minutes
C. 135 minutes
D. 270 minutes
What happens as the scatter of data values about the regression plane increases?
A. The standard error of estimate increases.
B. R2 increases.
C. (1 – R2) decreases.
D. The error sum of squares decreases.
The eighth decile:
A. contains at least 70 percent of the observations.
B. is the same as the 40th percentile.
C. is the same as the 70th percentile.
D. is the same as the 80th percentile.
A college professor noted that the grades of his students in an introductory statistics
class were normally distributed with a mean of 76.5 and a standard deviation of 9. If
67.36% of his students received grades of C or above, what is the minimum score of
those students receiving a grade of at least a C?
A. 67.36
B. 72.45
C. 66.56
D. 70.00
When a class interval is expressed as 100 up to 200, _________________________.
A. Observations with values of 100 are excluded from the class
B. Observations with values of 200 are included in the class
C. Observations with values of 200 are excluded from the class
D. The class interval is 99
In a two-way ANOVA with interaction, a significant interaction term indicates that
_________________.
A. the response variable is interactive
B. a blocking factor is present
C. both factors are unrelated
D. both factors have a combined effect on the response variable
The times (in minutes) that several underwriters took to review applications for similar
insurance coverage are 50, 230, 52, and 57. What is the median length of time required
to review an application?
A. 54.5
B. 141.0
C. 97.25
D. 109.0
In a goodness-of-fit test, the null hypothesis (no difference between sets of observed
and expected frequencies) is rejected when the ________________.
A. Computed chi-square is less than the critical value
B. Difference between the observed and expected frequencies is significantly large
C. Difference between the observed and expected frequencies is small
D. Difference between the observed and expected frequencies occurs by chance
The following table shows the sales for a plastics manufacturer recorded over the past
year. The seasonal indexes for each quarter are also provided. To track the trend for
these four quarters, use the indexes to deseasonalize the sales data.
Overall, sales are ___________.
When deciding on the number of observations to include in a sample, what would favor
larger sample sizes?
In testing the significance of Spearman’s rank-order coefficient, the null hypothesis is
_______________.
Using the following regression analysis:
What is the t test statistic to test the significance of the slope?
In a contingency table, multiplying the row total by the column total and dividing by
the ___________ computes the expected frequency for a cell.
For a trial, the number of possible outcomes for the binomial experiment is _____.
The Wilcoxon rank-sum uses the _____________ as the test statistic.
Refer to the following breakdown of responses to a survey of room cleanliness in a
hotel.
Draw a bar graph that illustrates the preceding frequency table.
The first three class marks for a frequency distribution of “weights of college men”
recorded to the nearest pound are 105, 115, and 125.
What are the class limits for the fourth class?
A probability distribution shows the outcomes of an experiment and the
___________________ of each one occurring.
We are interested in knowing if the following frequency distribution is normally
distributed. The population mean and standard deviation of the data are 600 and 160,
respectively.
What are the standard normal z-statistic class limits for the “800 up to 1000” class?