Test 1

Variables measured at the interval level cannot be used to classify, categorize, or rank order data.

False

Variables measured at the ordinal level cannot be used to classify or categorize data.

False

Which of the following is not a commonly used form of graphic representation?

Grouped frequency distribution

__________ typically are used to display continuous measures

Histograms

Which of the following is not a research strategy?

Interval data

The __________ is the score that occurs most frequently in a distribution.

Mode

Pie charts are particularly useful for what type of data

Nominal level data

In a frequency distribution, the cumulative percentage may be obtained by summing the _________ distribution.

Percentage

The median of a distribution is:

the middlemost point.

In a negatively skewed distribution:

the mode is larger than the mean.

In a positively skewed distribution:

the mode is smaller than the mean.

When constructing class intervals, it is important to take into consideration:

the pattern within the data that one wants to reveal.

Kurtosis refers to:

the peakedness of a distribution.

Variability refers to:

the spread of the sample scores

Skewness refers to:

the unequal distribution of extreme scores.

The square of the standard deviation is better known as:

the variance.

"Exhaustive" means that:

There is a category for every case that arises.

The concept of "mutually exclusive" means that:

There is one, and only one, category for every case.

Cumulative frequencies can only be used with variables measured at the ordinal or interval levels.

True

Data presented in the Uniform Crime Reports are summary measures.

True

Meta-analysis is the process of combining the results obtained in a number of previous studies and subjecting them all to a single significance test.

True

Nominal variables cannot logically be presented in a grouped frequency distribution.

True

Ordinal level data may be treated as interval if the ordered categories are evenly spaced.

True

The higher the standard deviation the greater the variation.

True

The mean cannot be meaningfully calculated for a nominal variable, such as gender.

True

The measures of central tendency one can use is determined by the variable's level of measurement.

True

The median is defined as the middlemost point in a distribution.

True

The mode can be applied to any set of data at the nominal, ordinal, or interval level of measurement.

True

The standard deviation is a more effective measure of variation than the range.

True

The standard deviation measures dispersion

True

Variables measured at the interval level are assigned a score

True

Variables measured at the nominal level only categorize or classify data.

True

When comparing between the variability of two characteristics that are measured in different units, social researchers should use the coefficient of variation.

True

The dependent variable affects the independent variable

False

The median is used for variables measured at the nominal level.

False

The standard deviation and range measure dispersion the same way.

False

The survey method is used to manipulate the independent variable.

False

The cumulative frequency is defined as the:

number of scores at or below any given score.

A researcher interested in the effects of release with aftercare for a small number of drug offenders. The number of additional months without drug use compared to non-aftercare programs is counted. The data on seven subjects are as follows: What is the standard deviation?

1.51

A police department's administration is interested in understanding the citizens in her city. The department randomly surveys 20 citizens and asks them to rate how satisfied they are on a scale of 1-9, where 1 is extremely dissatisfied 9 is extremely satisfied. Here is a frequency table of the collected data: Score 2,3,4,5,6,7,8,9. F 1,2,2,1,2,7,3,2. N=20 Calculate the standard deviation.

1.99

A researcher interested in the effects of release with aftercare for a small number of drug offenders. The number of additional months without drug use compared to non-aftercare programs is counted. The data on seven subjects are as follows: What is the variance?

2.28

A police department's administration is interested in understanding the citizens in her city. The department randomly surveys 20 citizens and asks them to rate how satisfied they are on a scale of 1-9, where 1 is extremely dissatisfied 9 is extremely satisfied. Here is a frequency table of the collected data: Score 2,3,4,5,6,7,8,9. F 1,2,2,1,2,7,3,2. N=20 Calculate the variance.

3.96

A class interval of 50-55 has lower and upper class limits of

49.5 and 55.5

A researcher interested in the effects of release with aftercare for a small number of drug offenders. The number of additional months without drug use compared to non-aftercare programs is counted. The data on seven subjects are as follows: What is the range?

5

Given the following test scores: 51, 58, 62, 62, 66, 74, 79, 79, 80, 80, 80, 80, 91, 93, 93, 93 The cumulative percent of a score of 79 is

50%

The retirement age of 9 police officers are provided below: 39, 41, 44, 50, 54, 56, 56, 56, 61 What is the mean?

50.78

The retirement age of 9 police officers are provided below: 39, 41, 44, 50, 54, 56, 56, 56, 61 What is the median?

54

The retirement age of 9 police officers are provided below: 39, 41, 44, 50, 54, 56, 56, 56, 61 What is the mode?

56

A police department's administration is interested in understanding the citizens in her city. The department randomly surveys 20 citizens and asks them to rate how satisfied they are on a scale of 1-9, where 1 is extremely dissatisfied 9 is extremely satisfied. Here is a frequency table of the collected data: Score 2,3,4,5,6,7,8,9. F 1,2,2,1,2,7,3,2. N=20 Calculate the mean.

6.2

A police department's administration is interested in understanding the citizens in her city. The department randomly surveys 20 citizens and asks them to rate how satisfied they are on a scale of 1-9, where 1 is extremely dissatisfied 9 is extremely satisfied. Here is a frequency table of the collected data: Score 2,3,4,5,6,7,8,9. F 1,2,2,1,2,7,3,2. N=20 Calculate the range.

7

A police department's administration is interested in understanding the citizens in her city. The department randomly surveys 20 citizens and asks them to rate how satisfied they are on a scale of 1-9, where 1 is extremely dissatisfied 9 is extremely satisfied. Here is a frequency table of the collected data: Score 2,3,4,5,6,7,8,9. F 1,2,2,1,2,7,3,2. N=20 What is the median?

7

A police department's administration is interested in understanding the citizens in her city. The department randomly surveys 20 citizens and asks them to rate how satisfied they are on a scale of 1-9, where 1 is extremely dissatisfied 9 is extremely satisfied. Here is a frequency table of the collected data: Score 2,3,4,5,6,7,8,9. F 1,2,2,1,2,7,3,2. N=20 What is the mode?

7

The following values represent the number of robberies that occur in a jurisdiction over 10 consecutive nights: 10, 12, 19, 5, 6, 8, 1, 13, 4, 7. What is the median?

7.5

Given the following test scores 51, 58, 62, 62, 66, 74, 79, 79, 80, 80, 80, 80, 91, 93, 93, 93 the cumulative frequency of a score of 79 is

8

The following values represent the number of robberies that occur in a jurisdiction over 10 consecutive nights: 10, 12, 19, 5, 6, 8, 1, 13, 4, 7.

8.5

What is the midpoint of the class interval 80-89?

84.5

Which of the following is true of the survey method?

All of the above statements are true (The research is retrospective. Surveys can accommodate a large number of dependent variables. Surveys can be highly representative).

Which of the following is true of quasi-experiments?

All of the above statements are true. (The research has no control group, Quasi-experiments are used more often than experiments in criminal justice research. Quasi-experiments are generally more ethically sound than true experiments.)

Criminal justice researches used measurement to

All the above. (Classify or categorize data, rank order data, assign a score).

Nominal measurement is used primarily to:

Classify or categorize data.

Studying newspapers and periodicals to investigate a hypothesis about reports of crime is an example of which method of investigation?

Content analysis

A researcher is interested in the influence of after-school supervision of juveniles on their at-risk behaviors. Fifty juveniles participated in an experiment in which twenty-five juveniles were supervised and twenty five were not supervised. A survey asked about their behaviors after school and the researcher recorded the total number of at-risk behaviors during a 2-week period. In this example, the group that is not being supervised is the ________ group.

Control

Deviation refers to:

Correct the distance of any score from the mean.

A distribution can only have one mode.

False

A positively skewed distribution has extreme scores on the left.

False

A symmetrical distribution has no variation.

False

Class intervals are always equal in size.

False

Scores that have a small standard deviation are relatively inconsistent.

False

The NCVS provides information on crimes reported to the police and crimes cleared by arrest

False

The difference between the highest and the lowest values in a distribution of scores is known as the:

Range

If the independent variable is in the rows of a cross-tabulation and the dependent variable is in the columns, which percents do we use for comparisons?

Row

A hypothesis is a(n):

Statement of the relationship between two or more variables.

Standard deviation can only be used for variables measured at which level?

The interval level

Which measure of central tendency is most appropriate for a skewed distribution?

The median

In a bimodal distribution of scores, central tendency is best measured by:

The mode

Which measure(s) of central tendency can be applied to nominal data?

The mode

What does the following formula define? Square root of sum of x^2 over n then minus x with a line over ^2

The standard deviation

Which of the following is a measure of variability?

The standard deviation

Which is not a measure of central tendency?

Variance

A synonym for variability is:

Width

The following values represent the number of robberies that occur in a jurisdiction over 10 consecutive nights: 10, 12, 19, 5, 6, 8, 1, 13, 4, 7. The sum of all deviations from the mean is equal to:

Zero

When organizing a frequency table for a variable measured at the ordinal level:

a & b

A comparison of the actual number of people who violate the speed limit to the total number of drivers is an example of _______.

a rate

When organizing a frequency table for a variable measured at the nominal level:

b & c

The standard deviation is a measure of __________.

b and c (Variability and Dispersion)

As a measure of central tendency, the mean:

can often be used for more advanced statistical operations

A researcher is interested in the influence of after-school supervision of juveniles on their at-risk behaviors. Fifty juveniles participated in an experiment in which twenty-five juveniles were supervised and twenty five were not supervised. A survey asked about their behaviors after school and the researcher recorded the total number of at-risk behaviors during a 2-week period. The number of at-risk behaviors is the __________ variable.

dependent

The range is useful for:

estimating the standard deviation

A researcher is interested in the influence of after-school supervision of juveniles on their at-risk behaviors. Fifty juveniles participated in an experiment in which twenty-five juveniles were supervised and twenty five were not supervised. A survey asked about their behaviors after school and the researcher recorded the total number of at-risk behaviors during a 2-week period. In this example, the group being supervised is the _________ group.

experimental

A researcher is interested in the influence of after-school supervision of juveniles on their at-risk behaviors. Fifty juveniles participated in an experiment in which twenty-five juveniles were supervised and twenty five were not supervised. A survey asked about their behaviors after school and the researcher recorded the total number of at-risk behaviors during a 2-week period. The manipulation of the subjects, either "supervision" or "no supervision," represents the:

independent variable.

The experimental method investigates the effect of a(n) ________ on a(n) ______.

independent variable; dependent variable

A symmetrical distribution that is extremely tall is

leptokurtic

The categories of __________-level distributions do not have to be listed in any particular order

nominal

The cumulative percentage is defined as the:

percentage of scores at or below a given value.

A distribution with a mean of 25, a median of 22.5, and a mode of 20, is said to be:

positively skewed

A distribution with a tail situated to the right is

positively skewed.

The __________ and the _________ are two of the most popular and useful methods of standardizing for size and comparing distributions.

proportion, percentage

Ordinal measurement is used primarily to:

rank order data.

The Greek symbol Σ represents the:

sum

A distribution with an equal mean, median, and mode is said to be:

symmetrical.