STATISTICS EXAM

ninapu

test_week_5_jar.docx

Home >Business & Finance homework help >Management homework help >STATISTICS EXAM

A linear regression:

· Correct Answer

gives a relationship between three variables that can be described by a line

· Correct Answer

gives a relationship between two variables that cannot be described by a line

· Correct Answer

contains only two variables

· Correct Answer

gives a relationship between two variables that can be described by a line

In a hypothesis test, a Type I error occurs when:

· Correct Answer

a false null hypothesis is rejected

· Correct Answer

a false null hypothesis is not rejected

· Correct Answer

a true null hypothesis is rejected

· Correct Answer

a true null hypothesis is not rejected

For small degrees of freedom, the chi-square distribution is:

· Correct Answer

skewed to the right

· Correct Answer

symmetric

· Correct Answer

skewed to the left

· Correct Answer

rectangular

What is the critical value of t for the hypothesis test?

· Correct Answer

2.441

· Correct Answer

2.733

· Correct Answer

2.449

· Correct Answer

2.738

A quantitative variable is the only type of variable that can:

· Correct Answer

have no intermediate values

· Correct Answer

assume numeric values for which arithmetic operations make sense

· Correct Answer

be used to prepare tables

· Correct Answer

be graphed

The alternative hypothesis is a claim about a:

· Correct Answer

parameter, where the claim is assumed to be true if the null hypothesis is declared false

· Correct Answer

parameter, where the claim is assumed to be true until it is declared false

· Correct Answer

statistic, where the claim is assumed to be true if the null hypothesis is declared false

· Correct Answer

statistic, where the claim is assumed to be false until it is declared true

Which of the following pairs of events are mutually exclusive?

· Correct Answer

Female and no

· Correct Answer

No and yes

· Correct Answer

Female and male

· Correct Answer

Female and yes

For a goodness-of-fit test, the frequencies obtained from the performance of an experiment are the:

· Correct Answer

objective frequencies

· Correct Answer

observed frequencies

· Correct Answer

expected frequencies

· Correct Answer

subjective frequencies

You toss a coin nine times and observe 3 heads and 6 tails. This event is a:

· Correct Answer

multinomial sample point

· Correct Answer

simple event

· Correct Answer

compound event

· Correct Answer

multiple outcome

Two paired or matched samples would imply that:

· Correct Answer

two data values are collected from the same source (elements) for two independent samples

· Correct Answer

two data values are collected from the same source (elements) for two dependent samples

· Correct Answer

data are collected on two variables from the elements of two independent samples

· Correct Answer

data are collected on one variable from the elements of two independent samples

The model y = A + Bx is a:

· Correct Answer

nonlinear model

· Correct Answer

probabilistic model

· Correct Answer

deterministic model

· Correct Answer

stochastic model

An error that occurs because of chance is called:

· Correct Answer

nonsampling error

· Correct Answer

probability error

· Correct Answer

sampling error

· Correct Answer

mean error

To make tests of hypotheses about more than two population means, we use the:

· Correct Answer

analysis of variance distribution

· Correct Answer

normal distribution

· Correct Answer

chi-square distribution

· Correct Answer

t distribution

The regression model y = A + Bx + e is:

· Correct Answer

a probabilistic model

· Correct Answer

a deterministic model

· Correct Answer

an exact relationship

· Correct Answer

a nonlinear model

A qualitative variable is the only type of variable that:

· Correct Answer

cannot be graphed

· Correct Answer

can assume an uncountable set of values

· Correct Answer

can assume numerical values

· Correct Answer

cannot be measured numerically

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:

· Correct Answer

less than to $110,000

· Correct Answer

greater than to $110,000

· Correct Answer

equal to $110,000

· Correct Answer

not equal to $110,000

The mean of a discrete random variable is the mean of its:

· Correct Answer

frequency distribution

· Correct Answer

second and third quartiles

· Correct Answer

percentage distribution

· Correct Answer

probability distribution

The graph of a cumulative frequency distribution is a(n):

· Correct Answer

ogive

· Correct Answer

frequency histogram

· Correct Answer

stem-and-leaf display

· Correct Answer

line graph

The graph of a cumulative frequency distribution is a(n):

· Correct Answer

ogive

· Correct Answer

frequency histogram

· Correct Answer

stem-and-leaf display

· Correct Answer

line graph

In a hypothesis test, a Type II error occurs when:

· Correct Answer

a true null hypothesis is rejected

· Correct Answer

a true null hypothesis is not rejected

· Correct Answer

a false null hypothesis is not rejected

· Correct Answer

a false null hypothesis is rejected

For a one-tailed test, the p-value is:

· Correct Answer

the area under the curve to the same side of the value of the sample statistic as is specified in the alternative hypothesis

· Correct Answer

twice the area under the curve between the mean and the observed value of the sample statistic

· Correct Answer

the area under the curve between the mean and the observed value of the sample statistic

· Correct Answer

twice the area under the curve to the same side of the value of the sample statistic as is specified in the alternative hypothesis

We can use the analysis of variance procedure to test hypotheses about:

· Correct Answer

two or more population means

· Correct Answer

the proportion of one population

· Correct Answer

the mean of one population

· Correct Answer

two or more population proportions

The p-value is the:

· Correct Answer

smallest significance level at which the null hypothesis can be rejected

· Correct Answer

smallest significance level at which the null hypothesis can be rejected

· Correct Answer

largest significance level at which the null hypothesis can be rejected

· Correct Answer

largest significance level at which the alternative hypothesis can be rejected

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:

· Correct Answer

sample proportion

· Correct Answer

sample distribution

· Correct Answer

sampling distribution

· Correct Answer

sample mean

In a one-way ANOVA, we analyze only one:

· Correct Answer

variable

· Correct Answer

population

· Correct Answer

sample

· Correct Answer

mean

The mean of a discrete random variable is its:

· Correct Answer

upper hinge

· Correct Answer

second quartile

· Correct Answer

box-and-whisker measure

· Correct Answer

expected value

You randomly select two households and observe whether or not they own a telephone answering machine. Which of the following is a simple event?

· Correct Answer

At least one of them owns a telephone answering machine.

· Correct Answer

Exactly one of them owns a telephone answering machine.

· Correct Answer

At most one of them owns a telephone answering machine.

· Correct Answer

Neither of the two owns a telephone answering machine.

A 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:

· Correct Answer

not equal to 30 minutes

· Correct Answer

equal to 30 minutes

· Correct Answer

less than or equal to 30 minutes

· Correct Answer

less than 30 minutes

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:

· Correct Answer

skewed to the right

· Correct Answer

not normal

· Correct Answer

approximately normal

· Correct Answer

skewed to the left

Which of the following assumptions is not required to use ANOVA?

· Correct Answer

The samples drawn from different populations are random and independent.

· Correct Answer

The populations from which the samples are drawn have the same variance.

· Correct Answer

The populations from which the samples are drawn are (approximately) normally distributed.

· Correct Answer

All samples are of the same size.

What is the critical value of z for the hypothesis test?

· Correct Answer

-2.05

· Correct Answer

-2.17

· Correct Answer

-2.33

· Correct Answer

-1.96