1An error that occurs because of chance is called:
mean error
probability error
sampling error
nonsampling error
2For a goodness-of-fit test, the frequencies obtained from the performance of an experiment are the:
expected frequencies
objective frequencies
observed frequencies
subjective frequencies
3In a hypothesis test, a Type I error occurs when:
a true null hypothesis is rejected
a true null hypothesis is not rejected
a false null hypothesis is rejected
a false null hypothesis is not rejected
4Which of the following assumptions is not required to use ANOVA?
The populations from which the samples are drawn have the same variance.
The samples drawn from different populations are random and independent.
All samples are of the same size.
The populations from which the samples are drawn are (approximately) normally distributed.
5A researcher wants to test if elementary school children spend less than 30 minutes per day on homework. The alternative hypothesis for this example will be that the population mean is:
not equal to 30 minutes
less than or equal to 30 minutes
less than 30 minutes
equal to 30 minutes
6The model y = A + Bx is a:
nonlinear model
deterministic model
probabilistic model
stochastic model
7A sample of 16 from a population produced a mean of 86.9 and a standard deviation of 14.3. A sample of 18 from another population produced a mean of 75.4 and a standard deviation of 15.9. Assume that the two populations are normally distributed and the standard deviations of the two populations are equal. The null hypothesis is that the two population means are equal, while the alternative hypothesis is that the mean of the first population is greater than the man of the second population. The significance level is 1%.
What is the critical value of t for the hypothesis test?
2.441
2.733
2.449
2.738
8Two events are independent if the occurrence of one event:
means that the second event cannot occur.
does not affect the probability of the occurrence of the other event.
affects the probability of the occurrence of the other event.
means that the second event is certain to occur.
9You toss a coin nine times and observe 3 heads and 6 tails. This event is a:
simple event
multinomial sample point
multiple outcome
compound event
10The p-value is the:
smallest significance level at which the null hypothesis can be rejected
largest significance level at which the alternative hypothesis can be rejected
smallest significance level at which the null hypothesis cannot be rejected
largest significance level at which the null hypothesis can be rejected
11 A researcher wants to test if the mean annual salary of all lawyers in a city is different than $110,000. The null hypothesis for this example will be that the population mean is:
not equal to $110,000
greater than to $110,000
less than to $110,000
equal to $110,000
12 To make tests of hypotheses about more than two population means, we use the:
analysis of variance distribution
chi-square distribution
t distribution
normal distribution
13 In a game of four-handed Hearts, all 52 cards of a standard deck are dealt, so that each player starts each round with 13 cards in a hand. Suppose player A’s hand has three clubs, six diamonds, two hearts, and two spades. What is the relative frequency of spades, rounded to two decimal places, dealt to player A?
0.25
0.75
1.5
0.15
14 In a one-way ANOVA, we analyze only one:
population
variable
mean
Sample
15 The regression model y = A + Bx + e is:
an exact relationship
a nonlinear model
a deterministic model
a probabilistic model
16 In a hypothesis test, a Type II error occurs when:
a false null hypothesis is not rejected
a false null hypothesis is rejected
a true null hypothesis is rejected
a true null hypothesis is not rejected
17 A qualitative variable is the only type of variable that:
can assume an uncountable set of values
cannot be graphed
can assume numerical values
cannot be measured numerically
18 A continuous random variable x has a right-skewed distribution with a mean of 80 and a standard deviation of 12. The sampling distribution of the sample mean for a sample of 50 elements taken from this population is:
not normal
approximately normal
skewed to the right
skewed to the left
19 For a one-tailed test, the p-value is:
twice the area under the curve between the mean and the observed value of the sample statistic
twice the area under the curve to the same side of the value of the sample statistic as is specified in the alternative hypothesis
the area under the curve between the mean and the observed value of the sample statistic
the area under the curve to the same side of the value of the sample statistic as is specified in the alternative hypothesis
20 A quantitative variable is the only type of variable that can:
be graphed
have no intermediate values
assume numeric values for which arithmetic operations make sense
be used to prepare tables
21 If you divide the number of elements in a sample with a specific characteristic by the total number of elements in the sample, the dividend is the:
sample proportion
sampling distribution
sample mean
sample distribution
22 We can use the analysis of variance procedure to test hypotheses about:
two or more population means
the proportion of one population
two or more population proportions
the mean of one population
23 Which of the following pairs of events are mutually exclusive?
Female and no
Female and male
Male and yes
Female and yes
24 The mean of a discrete random variable is the mean of its:
probability distribution
frequency distribution
percentage distribution
second and third quartiles
25 In a survey regarding job satisfaction, 574 in a sample of 934 female job-holders stated that they are satisfied with their jobs, while 500 in a sample of 755 male job-holders stated that they are satisfied with their jobs. The null hypothesis is that the proportions of all female and male job-holders who are satisfied with their jobs are the same. The alternative hypothesis is that the proportion of female job-holders who are satisfied with their jobs is lower than the proportion of male job-holders stated who are satisfied with their jobs. The significance level is 2.5%.
What is the critical value of z for the hypothesis test?
-2.05
-1.96
-2.17
-2.33
26 For small degrees of freedom, the chi-square distribution is:
skewed to the right
rectangular
skewed to the left
Symmetric
27 The mean of a discrete random variable is its:
second quartile
upper hinge
expected value
box-and-whisker measure
28 A linear regression:
gives a relationship between two variables that can be described by a line
gives a relationship between two variables that cannot be described by a line
contains only two variables
gives a relationship between three variables that can be described by a line
29 Two paired or matched samples would imply that:
two data values are collected from the same source (elements) for two independent samples
data are collected on two variables from the elements of two independent samples
data are collected on one variable from the elements of two independent samples
two data values are collected from the same source (elements) for two dependent samples
30 The alternative hypothesis is a claim about a:
parameter, where the claim is assumed to be true until it is declared false
parameter, where the claim is assumed to be true if the null hypothesis is declared false
statistic, where the claim is assumed to be true if the null hypothesis is declared false
statistic, where the claim is assumed to be false until it is declared true