In a completely randomized experimental design, 7 experimental units were used for
the first treatment, 9 experimental units for the second treatment, and 14 experimental
units for the third treatment. Part of the ANOVA table for this experiment is shown
below.
Exhibit 12-3
In order to determine whether or not a particular medication was effective in curing the
common cold, one group of patients was given the medication, while another group
received sugar pills. The results of the study are shown below.
We are interested in determining whether or not the medication was effective in curing
the common cold.
Refer to Exhibit 12-3. The hypothesis is to be tested at the 5% level of significance. The
critical value from the table equals
a. 3.84
b. 7.81
c. 5.99
d. 9.34
In order to compute a binomial probability we must know all of the following except
a. the probability of success
b. the number of elements in the population
c. the number of trials
d. the value of the random variable
“DRUGS R US” is a large manufacturer of various kinds of liquid vitamins. The quality
control department has noted that the bottles of vitamins marked 6 ounces vary in
content with a standard deviation of 0.3 ounces. Assume the contents of the bottles are
normally distributed.
a. What percentage of all bottles produced contains more than 6.51 ounces of vitamins?
b. What percentage of all bottles produced contains less than 5.415 ounces?
c. What percentage of bottles produced contains between 5.46 and 6.495 ounces?
d. Ninety-five percent of the bottles will contain at least how many ounces?
e. What percentage of the bottles contains between 6.3 and 6.6 ounces?
Excel’s ____ function can be used to conduct the Wilcoxon signed-rank test.
a. POISSON.DIST
b. BINOM.DIST
c. CHISQ.DIST.RT
d. NORM.S.DIST
Partial results of a study follow in a crosstabulation of column percentages.
Exhibit 12-2
Last school year, the student body of a local university consisted of 30% freshmen, 24%
sophomores, 26% juniors, and 20% seniors. A sample of 300 students taken from this
year’s student body showed the following number of students in each classification.
We are interested in determining whether or not there has been a significant change in
the classifications between the last school year and this school year.
Refer to Exhibit 12-2. The hypothesis is to be tested at the 5% level of significance. The
critical value from the table equals
a. 1.645
b. 1.96
c. 2.75
d. 7.815
Which of the following is an example of a nonprobability sampling technique?
a. simple random sampling
b. stratified random sampling
c. cluster sampling
d. judgment sampling
Exhibit 11-5
Refer to Exhibit 11-5. The test statistic for this problem equals
a. .63
b. 12.68
c. 13.33
d. 13.66
If a hypothesis test has a Type I error probability of .05, that means
a. if the null hypothesis is false, it will not be rejected 5% of the time
b. if the null hypothesis is false, it will be rejected 5% of the time
c. if the null hypothesis is true, it will not be rejected 5% of the time
d. if the null hypothesis is true, it will be rejected 5% of the time
In a regression model involving 46 observations, the following estimated regression
equation was obtained.
= 17 + 4x1 – 3x2 + 8x3 + 5x4 + 8x5
For this model, SST = 3410 and SSE = 510.
Exhibit 9-5
Assume population is normally distributed.
Refer to Exhibit 9-5. The p-value is equal to
a. -0.0166
b. 0.0166
c. 0.0332
d. 0.9834
A one-tailed test is a
a. hypothesis test in which rejection region is in both tails of the sampling distribution
b. hypothesis test in which rejection region is in one tail of the sampling distribution
c. hypothesis test in which rejection region is only in the lower tail of the sampling
distribution
d. hypothesis test in which rejection region is only in the upper tail of the sampling
distribution
The following is a frequency distribution for the ages of a sample of employees at a
local company.
a. Determine the average age for the sample.
b. Compute the variance.
c. Compute the standard deviation.
d. Compute the coefficient of variation.
If all the points of a scatter diagram lie on the least squares regression line, then the
coefficient of determination for these variables based on this data is
a. 0
b. 1
c. either 1 or -1, depending upon whether the relationship is positive or negative
d. could be any value between -1 and 1
Compute the weighted mean for the following data.
A simple random sample from a process (an infinite population) is a sample selected
such that
a. each element selected comes from the same population
b. each element is selected independently
c. each element selected comes from the same population and each element is selected
independently
d. the probability of being selected changes
A manufacturer wants to estimate the proportion of defective items that are produced by
a certain machine. A random sample of 50 items is taken. Which Excel function would
not be appropriate to construct a confidence interval estimate?
a. NORM.S.INV
b. COUNTIF
c. STDEV
d. All are appropriate.
For a two-tailed hypothesis test with a test statistic value of z = 2.05, the p-value is
a. .0101
b. .0202
c. .0404
d. .4899