Deck 3: Frequency Distributions

Question 1

A psychologist is interested in the social interactions of preschool children. She measures the number of verbal interactions that each child at a preschool engages in during a day. Here is the frequency distribution of the data. The 50^th percentile point is _________.

A) 65.50
B) 62.15
C) 65.00
D) 74.00

Answer 1

65.00

Question 2

A researcher has collected some data on the amount of time in seconds (to the nearest 0.1 second) that it took trained rats to run through a maze. The data is shown below arranged in a frequency distribution of grouped scores. The cumulative percentage for the interval 5.2-5.5 is _________.

A) 13.89%
B) 47.22%
C) 22.22%
D) 36.11%

Answer 2

36.11%

Question 3

A psychologist is interested in the social interactions of preschool children. She measures the number of verbal interactions that each child at a preschool engages in during a day. Here is the frequency distribution of the data. The cumulative frequency for the interval 46-55 is _________.

A) 4
B) 9
C) 0.29
D) 13

Answer 3

13

Question 4

The distribution of scores of high school seniors on a sixth grade math test would probably be _________.

A) positively skewed
B) negatively skewed
C) normal
D) symmetrical but not normal

Question 5

A psychologist is interested in the social interactions of preschool children. She measures the number of verbal interactions that each child at a preschool engages in during a day. Here is the frequency distribution of the data. The real limits of the interval 56-65 are _________.

A) 56.5-65.5
B) 55.5-65.5
C) 55-67
D) 56-65

Question 6

If a curve is symmetrical, _________.

A) most of the scores fall at the lower values of the X axis
B) most of the scores fall at the higher values of the X axis
C) if folded in half, the two sides of the curve coincide
D) most of the scores fall at the higher values of the Y axis

Question 7

A researcher has collected some data on the amount of time in seconds (to the nearest 0.1 second) that it took trained rats to run through a maze. The data is shown in the frequency distribution of grouped scores that follows. The percentile rank of a score of 6.5 is _________.

A) 61.81%
B) 59.72%
C) 9.37%
D) 9.03%

Question 8

A psychologist is interested in the social interactions of preschool children. She measures the number of verbal interactions that each child at a preschool engages in during a day. The resulting data are shown in the following frequency distribution. The relative frequency for the interval 76-85 is _________.

A) 0.13
B) 0.09
C) 0.16
D) 0.11

Question 9

Assume your task is to group the raw scores given below into a frequency distribution of approximately 12 intervals of equal width. The interval containing the most scores is _________.

A) 60-64
B) 62-66
C) 62-67
D) 60-65

Question 10

A researcher has collected some data on the amount of time in seconds (to the nearest 0.1 second) that it took trained rats to run through a maze. The data is shown below arranged in a frequency distribution of grouped scores. The 75th percentile point is _________.

A) 6.42
B) 6.87
C) 6.82
D) 6.47

Question 11

A researcher has collected some data on the amount of time in seconds (to the nearest 0.1 second) that it took trained rats to run through a maze. The data is shown below arranged in a frequency distribution of grouped scores. The real limits of the interval 6.4-6.7 are _________.

A) 6.3-6.8
B) 6.4-6.7
C) 6.35-6.75
D) 6.45-6.75

Question 12

Assume your task is to group the raw scores given below into a frequency distribution of approximately 12 intervals of equal width. The value of i is _________.

A) 5.5
B) 4
C) 6
D) 5

Question 13

A psychologist is interested in the social interactions of preschool children. She measures the number of verbal interactions that each child at a preschool engages in during a day. The resulting data are shown in the following frequency distribution. The percentile rank of a score of 40 is _________.

A) 16.33%
B) 16.00%
C) 9.67%
D) 16.67%

Question 14

A researcher has collected some data on the amount of time in seconds (to the nearest 0.1 second) that it took trained rats to run through a maze. The data is shown in the frequency distribution of grouped scores that follows. The relative frequency for the interval 5.2-6.6 is _________.

A) 0.03
B) 0.14
C) 0.11
D) 13

Question 15

If a large psychology class took a test on theoretical biophysics, the distribution of scores would probably be _________.

A) positively skewed
B) symmetrical
C) negatively skewed
D) ogival

Question 16

Assume your task is to group the raw scores given below into a frequency distribution of approximately 12 intervals of equal width. The lowest class interval is _________.

A) 30-35
B) 32-36
C) 32-37
D) 30-34

Question 17

An accountant is preparing a graph showing the number of sports cars of various makers purchased this year. The number will be plotted on the ordinate and the various manufacturers on the abscissa. The proper type of graph for this data is a(n) _________.

A) frequency polygon
B) histogram
C) bar graph
D) ogive

Question 18

Assume your task is to group the raw scores given below into a frequency distribution of approximately 12 intervals of equal width. The highest frequency for any interval is _________.

A) 6
B) 8
C) 10
D) 7

Question 19

A psychologist is interested in the social interactions of preschool children. She measures the number of verbal interactions that each child at a preschool engages in during a day. Here is the frequency distribution of the data. The cumulative % for the interval 46-55 is _________.

A) 8.89%
B) 20.00%
C) 0.64%
D) 28.89%

Question 20

A researcher has collected some data on the amount of time in seconds (to the nearest 0.1 second) that it took trained rats to run through a maze. The data is shown below arranged in a frequency distribution of grouped scores. The cumulative frequency for the interval 6.0-6.3 is _________.

A) 20
B) 0.57
C) 17
D) 57

Question 21

Given the distribution of grouped scores shown in the following table. What percentage of cases fall within the class interval containing the most cases?

A) 18.71
B) 26.62
C) 67.63
D) 41.01

Question 22

In graphing frequency distributions, _________ is usually plotted on the abscissa.

A) frequency
B) class width
C) the score value
D) interval width

Question 23

What indicates the proportion of the total number of scores that occurred in each interval?

A) relative frequency distribution
B) cumulative frequency distribution
C) cumulative percentage distribution
D) none of these

Question 24

What indicates the number of scores that fell below the upper real limit of each interval?

A) relative frequency distribution
B) cumulative frequency distribution
C) cumulative percentage distribution
D) none of these

Question 25

Given the distribution of grouped scores shown in the following table. How many occurrences are there for the interval 60-69?

A) 115
B) 37
C) 15
D) 21

Question 26

The purpose of a frequency distribution is to _________.

A) present scores and their frequency of occurrence
B) present data in a more meaningful way than just presenting the raw scores
C) provide more information than a graph
D) all of the above
E) a and b

Question 27

If i = 7, the scores are integer, and the minimum value of the distribution of scores is 8, what would the lowest class interval be?

A) 0-7
B) 7-14
C) 8-16
D) 8-15
E) 7-13

Question 28

The range of a set of scores with a maximum value of 92 and a minimum value of 26 is _________.

A) 65
B) 66
C) 67
D) 92

Question 29

The true limits of 7.0 are _________.

A) 6.5-7.5
B) 6.0-8.0
C) 7.0-7.1
D) 6.95-7.05

Question 30

Which of the following is (are) not a symmetrical distribution?

A) a bell-shaped curve
B) a J-shaped curve
C) a rectangular curve
D) an inverted U-shaped curve
E) a bell-shaped, J-shaped, and an inverted U-shaped curve

Question 31

Interval or ratio data may be plotted as a _________.

A) bar graph
B) histogram
C) frequency polygon
D) b and c

Question 32

Given the distribution of grouped scores shown in the following table. How many occurrences fall below the upper real limit of the interval 70-79?

A) 115
B) 137
C) 130
D) 15

Question 33

If the range of a distribution were 89 and the data were reported as whole numbers, what would the width of the class interval be if one chose to group the distribution into approximately 14 class intervals?

A) 14
B) 89
C) 5
D) 6
E) 7

Question 34

Given the distribution of grouped scores shown in the following table. What is the cumulative percentage below the lower real limit of the interval 90-99?

A) 137
B) 5.04
C) 100.00
D) 98.56

Question 35

Given the distribution of grouped scores shown in the following table. N equals _______.

A) 139
B) 145
C) 137
D) 135

Question 36

Your new Mercedes weighs 1850 kilograms when measured to the nearest kilogram. The real limits of its weight are _________.

A) 1800-1900
B) 1840-1860
C) 1849-1851
D) 1849.5-1850.5

Question 37

When constructing bar graphs, the bars do not touch each other because _______.

A) it looks nicer
B) it emphasizes the lack of quantitative relationship between the categories
C) it is traditional
D) none of these

Question 38

A distribution which has a predominance of scores at the lower values of the distribution and which tails off at the higher end is _______.

A) positively skewed
B) negatively skewed
C) normally distributed
D) symmetrical

Question 39

In a frequency polygon the points are plotted over _______ at a height corresponding to the frequency of the interval.

A) the midpoint of each interval
B) the lower real limit
C) the upper real limit
D) none of these

Question 40

When individual scores are combined into groups, _________.

A) information is lost
B) data is added
C) a meaningful visual display can result depending on the interval width
D) information is lost and data is added

Question 41

All frequency distributions should be of grouped scores.

Question 42

In grouping scores, the wider the intervals, the more information that is lost.

Question 43

Consider the following score diagram. This score diagram is called a _________.

A) histogram
B) frequency polygon
C) box plot
D) stem and leaf diagram

Question 44

In constructing a frequency distribution of grouped scores, i should be rounded to one more decimal place than in the raw scores.

Question 45

If a curve is negatively skewed, most of the scores occur at the higher values and the curve tails off toward the lower end of the horizontal axis.

Question 46

A bell shaped curve is an example of a skewed distribution.

Question 47

Consider the following stem-and-leaf diagram. This score distribution is _______.

A) positively skewed
B) negatively skewed
C) symmetrical
D) neither skewed or symmetrical

Question 48

The percentile point for a distribution of scores must have a value equal to one of the scores.

Question 49

A percentile point is defined as _________.

A) the percentage of scores that fall below a specified scale value
B) the value on the measurement scale below which a specified percentage of the scores fall
C) P₅₀
D) P₂₀

Question 50

In constructing a frequency distribution of grouped scores, the intervals must be continuous and mutually exclusive.

Question 51

If the frequency of any score is zero, it should not be listed in a frequency distribution.

Question 52

The percentile rank of a score is defined as _________.

A) the percentage of scores that fall below the score in question
B) the percentage of scores that fall below a specified scale value
C) the number of scores that fall below the score in question
D) a and b

Question 53

Given the distribution of grouped scores shown in the following table. What is the value of i ?

A) 10
B) 9
C) 9.5
D) 10.5

Question 54

In a frequency distribution of grouped scores, all intervals should be of exactly the same width.

Question 55

A curve is negatively skewed when _________.

A) most of the scores occur at the lower end of the horizontal axis and the curve tails off toward the higher end
B) it is folded in half and the two sides do not coincide
C) most of the scores occur at the higher end of the horizontal axis and the curve tails off toward the lower end.
D) b and c

Question 56

A histogram is like a bar graph except with a histogram the bars don't touch each other.

Question 57

A frequency polygon results in a curve that looks as though the scores were continuously distributed.

Question 58

Given the distribution of grouped scores shown in the following table. The 50th percentile point equals _________.

A) 53.38
B) 52.54
C) 52.88
D) 54.31

Question 59

Consider the following stem-and-leaf diagram. If the numbers in the left column are deciles, the median of the distribution falls in the range of _______.

A) 80 - 90
B) 60 - 69
C) 70 - 79
D) can't answer; need more information

Question 60

Given the distribution of grouped scores shown in the following table. The percentile rank of a score of 41 equals _________.

A) 25.42%
B) 25.11%
C) 16.47%
D) 29.42%

Question 61

When constructing the frequency distribution it is customary to show the real limits of the class intervals in the table.

Question 62

A "U" shaped distribution is an example of a symmetrical distribution.

Question 63

A frequency distribution of grouped scores is used for distributions that have relatively few scores to stretch them out.

Question 64

A frequency distribution presents the score values and their frequency of occurrence.

Question 65

A relative frequency distribution indicates the number of scores that fall below the upper real limit of each interval.

Question 66

For the frequency distribution shown in the following table, N = 4.

Question 67

When constructing frequency distributions there must be 12 class intervals.

Question 68

One reason for constructing frequency distributions is to be able to visualize the shape of the distribution.

Question 69

In a cumulative percentage curve, percentage is shown on the abscissa.

Question 70

To determine the width of the class interval, i, divide the range by the number of class intervals.

Question 71

Bar graphs are generally used for nominal or ordinal data and histograms are generally used for interval or ratio data.

Question 72

A stem and leaf diagram contains more information than a histogram.

Question 73

When constructing a distribution of grouped scores, the only requirement regarding the lower limit of the lowest interval is that the interval includes the lowest score in the distribution.

Question 74

In a frequency distribution the more intervals the better, regardless of whether some intervals have zero frequency.

Question 75

A cumulative frequency distribution indicates the number of scores which fell below the upper real limit of each interval.

Question 76

A relative frequency distribution indicates the total number of scores which occurred in each interval.

Question 77

The vertical axis, i.e., the Y axis of a graph, is called the abscissa.

Question 78

For the frequency distribution shown in the following table, = 25.

Question 79

Given a distribution of grouped scores, if an interval is shown as 2-8, the interval is 6 units wide

Question 80

The percentile rank of a score is equal to the percentage of scores in the distribution that fall below the score in question.