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1

All of the following are measures of central tendency except the ____________.

Mode
Median
Range
Mean

Range

2

If the mean is greater than the median, then the distribution is ___________.

Skewed right
Skewed left
Bimodal
Symmetrical

Skewed Right

3

As a measure of variation, the sample ___________ is easy to understand and compute. It is based on the two extreme values and is therefore a highly unstable measure.

Range

4

If a population distribution is skewed to the right, then, given a random sample from that population, one would expect that the ____________.

Median would be less than the mean

5

A quantity that measures the variation of a population or a sample relative to its mean is called the ____________.


Coefficient of variation

6

As the coefficient of variation _______________ risk ______________.

Increases, Increases

7

Which of the following is influenced the least by the occurrence of extreme values in a sample?

Median

8

The average of the squared deviations of the individual population measurement from the population mean is the ___________.

Variance

9

A normal population has 99.73 percent of the population measurements within __________ standard deviations of the mean.

Three

10

A measure of the strength of the linear relationship between x and y that is dependent on the units in which x and y are measured.

Covariance

11

If the mean, median, and mode for a given population all equal 25, then we know that the shape of the distribution of the population is ____________.

Symmetrical

12

Determine whether the two events are mutually exclusive.

Consumer with an unlisted phone number and a consumer who does not drive


Not mutually exclusive

13

The simultaneous occurrence of events A and B is represented by the notation _______________.

A "junction" B

14

The set of all possible experimental outcomes is called a(n) ____________.

Sample space

15

If events A and B are independent, then P(A|B) is equal to _____________.


P(A)

16

A(n) _______________ probability is a probability assessment that is based on experience, intuitive judgment, or expertise.

Subjective

17

Determine whether the two events are mutually exclusive.

Unmarried person and a person with an employed spouse

Mutually exclusive

18

If events A and B are mutually exclusive, calculate P(A|B).


0


Mutually exclusive events have intersection = 0. Therefore, the conditional probability is also 0.

19

Determine whether the two events are mutually exclusive.

Voter who favors gun control and an unregistered voter


Mutually exclusive

20

The ___________ of two events X and Y is another event that consists of the sample space outcomes belonging to either event X or event Y or both events X and Y.


Union

21

If two events are independent, we can _____________ their probabilities to determine the intersection probability.

Multiply

22

Events that have no sample space outcomes in common, and therefore cannot occur simultaneously, are ____________.

Mutually exclusive

23

A(n) ____________ is the probability that one event will occur given that we know that another event already has occurred.

Conditional probability

24

A card is drawn from a standard deck. What is the probability the card is an ace, given that it is a club?

1/13

25

Two mutually exclusive events having positive probabilities are ______________ dependent.

always

26

If P(A|B) = .2 and P(B) = .8, determine the intersection of events A and B.

.16

27

Temperature (in degrees Fahrenheit) is an example of a(n) ________ variable.


Interval

28

An identification of police officers by rank would represent a(n) ____________ level of measurement

Ordinal

29

A(n) ___________________ variable is a qualitative variable such that there is no meaningful ordering or ranking of the categories.

Nominal

30

Which of the following is a qualitative variable?


Air Temperature



Bank Account Balance



Daily Sales in a Store



Whether a Person Has a Traffic Violation



Value of Company Stock

Whether a Person Has a Traffic Violation

31

_____ refers to describing the important aspects of a set of measurements.

Descriptive statistics

32

The weight of a chemical compound used in an experiment that is obtained using a well-adjusted scale represents a(n) _____________ level of measurement.

Ratio

33

College entrance exam scores, such as SAT scores, are an example of a(n) ________________ variable.

Interval

34

Jersey numbers of soccer players are an example of a(n) ___________ variable.

nominal

35

Examining all population measurements is called a ____.

census

36

A _____ is a subset of the units in a population.

sample

37

______________ is the science of using a sample to make generalizations about the important aspects of a population.

Statistical Inference

38

The variable "home ownership" can take on one of two values, 1 if the person living in a home owns the home and zero if the person living in a home does not own the home. This is an example of a discrete random variable.

True

39

A discrete random variable may assume a countable number of outcome values.

True

40

The standard deviation of a discrete random variable measures the spread of the population of all possible values of x.

true

41

The expected value of the discrete random variable x is the population mean.

true

42

For a discrete probability distribution, the value of p(x) for each value of x falls between −1 and 1.


False


Response Feedback:
Probability values can only fall between 0 and 1.

43

For a random variable X, the mean value of the squared deviations of its values from their expected value is called its ____________.

Variance

44

The time (in seconds) it takes for an athlete to run 50 meters is an example of a continuous random variable

True

45

A probability distribution of a discrete random variable is expressed as a table, graph, or ___________.

Formula

46

Which of the following is not a discrete random variable?



The number of minutes required to run 1 mile.



The number of defects in a sample selected from a population of 100 products.



The number of criminals found in a five-mile radius of a neighborhood.

The number of times a light changes red in a 10-minute cycle.


The number of minutes required to run 1 mile.