Statistics Chapter 2
When cumulating frequencies from the bottom up, the data are discussed in terms of at most less than at or below all of the above
all of the above
To determine the interval width, we divide the ________ by the number of intervals. observed range exclusive range real range all of the above
real range
Grouped data are distributed into ________, whereas ungrouped data are distributed into ________. intervals; statistics statistics; intervals intervals; categories categories; intervals
intervals; categories
The ________ is the percentage of scores with values that fall below a specified score in a distribution, is called the: percentile rank interval relative frequency percentile point
percentile rank
The sum of relative frequencies for each interval is _____. 1.00 100% equal to the total number of scores in a distribution both A and B
1.00
A researcher finds that 12% of participants make between 3-5 visits to a physician each year. What are the real limits for this interval? 3-5 2.5-5.5 2.5-3.5 equal to the sum of the products for the previous interval
2.5-5.5
A researcher reports that 12 persons in a sample of 60 reported getting between 4 and 6 hours of sleep per night. What is the relative percentage for this interval? 24% 22% 20% There is not enough information to answer this question.
20%
The following frequency distribution is an example of Household TVs f(x) 5 4 4 23 3 20 2 29 1 30 0 8 grouped data ungrouped data categorical data both B and C
both B and C
A relative frequency distribution is appropriate when there are large frequency counts in each interval the data are grouped into relatively small intervals there are open classes the interval width is too large
there are large frequency counts in each interval
What is the percentile point at the 80th percentile in the following distribution? Frequency Percentile Rank 9-11 100% 6-8 80% 3-5 40% 0-2 20% 2 6 7 8
8
State the type of graphical display for Graph A and Graph B. Refer to the Image. A is a bar chart; B is a histogram. B is a bar chart; A is a histogram. Both graphs are bar charts. Both graphs are histograms.
B is a bar chart; A is a histogram.
Grouped data can be distributed as a range of values with upper and lower boundaries into intervals all of the above
all of the above
A researcher distributes frequencies into the following intervals: 1-10, 11-20, 21-30, 31-40, 41-50, and 51 and above. What is wrong with this frequency distribution? The interval width is too small. The interval width is unequal. The class intervals overlap. One interval is an open class.
One interval is an open class.
State the problem with this simple frequency distribution. Intervals Frequency 8-10 4 6-8 7 4-6 3 2-4 6 0-2 9 The interval width is too small. The interval width is unequal. The class intervals overlap. The number of intervals is too small.
The class intervals overlap.
Which of the following is NOT a rule for constructing a simple frequency distribution? The number of intervals should equal the number of values measured. Each interval is equidistant. No class interval overlaps. Values are rounded to the same degree of accuracy measured in the original data.
The number of intervals should equal the number of values measured.
When cumulating frequencies from the top down, the data are discussed in terms of greater than at or above at least all of the above
all of the above
A researcher wants to determine how many participants will take less than 24 seconds to complete a cognitive performance task. If he constructs a frequency distribution for these data, what type of distribution would be most appropriate to answer his question? a simple frequency distribution a relative frequency distribution a cumulative frequency distribution from the bottom up a cumulative frequency distribution from the top down
a cumulative frequency distribution from the bottom up
A psychologist wants to know how many of her clients continue with therapy for at least 12 days. If she constructs a frequency distribution for these data, what type of distribution would be most appropriate to answer her question? a cumulative frequency distribution from the bottom up a cumulative frequency distribution from the top down a simple frequency distribution a relative frequency distribution
a cumulative frequency distribution from the top down
A percentile is a percentile point a value between -1 and + a raw score multiplied times 100 only used with ungrouped data
a percentile point
A researcher distributes frequencies into the following classes: absent, tardy, present. What type of data are distributed? nominal data qualitative data ungrouped data all of the above
all of the above
A simple frequency distribution can be used to summarize grouped data can be used to summarize ungrouped data summarizes the frequency of scores in a given category or range all of the above
all of the above
The following is a simple frequency distribution table. Suppose we convert this table to a cumulative frequency distribution. The frequencies in each interval of the cumulative frequency distribution would be Intervals Frequency 17-20 5 13-16 3 9-12 2 5-8 4 1-4 6 20 5, 8, 10, 14, 20 (top down summary) 6, 10, 12, 15, 20 (bottom up summary) both A and B, depending on how the data were summarized It is not possible to summarize the data using a cumulative frequency distribution.
both A and B, depending on how the data were summarized
Grouped data are to ungrouped data as quantitative is to qualitative qualitative is to quantitative inferential is to descriptive descriptive is to inferential
quantitative is to qualitative
To construct a pie chart, first distribute the data as cumulative percentages relative percentages cumulative frequencies cumulative relative percentages
relative percentages
The following is a simple frequency distribution table. If we convert this frequency distribution to relative percentages, which of the following gives the corresponding percentages in each interval listed from the top down. Intervals Frequency 44-46 6 41-43 4 38-40 5 35-37 10 32-34 5 30 20%, 33%, 50%, 67%, 100% 0.2, 0.13, 0.17, 0.33, 0.17 20%, 13%, 17%, 33%, 17% 6, 10, 15, 25, 30
20%, 13%, 17%, 33%, 17%
What is the percentile point at the 50th percentile for the following distribution? Intervals Frequency 31-35 9 26-30 11 21-25 12 35-37 8 21 23.5 25 25.5
25
As a general rule, a simple frequency distribution should have between 3 and 6 intervals 5 and 10 intervals 8 and 12 intervals 5 and 20 intervals
5 and 20 intervals
What is the percentile point at the 90th percentile in the following distribution? Frequency Percentile Rank 9-11 100% 6-8 80% 3-5 40% 0-2 20% 9 10 9.5 10.5
9.5
Fill in the missing values for A and B in this frequency distribution table: Intervals Frequency 6.0-6.6 12 5.3-5.9 7 4.6-5.2 B 3.9-4.5 10 A-3.8 8 50 A = 3.2, B = 13 A = 3.1, B = 14 A = 3.3, B = 13 There is not enough information to complete this table.
A = 3.2, B = 13
A researcher distributes frequencies into the following intervals: 3-6, 7-10, 11-15, 16-18, 19-22, and 23-26. What is wrong with this frequency distribution? The interval width is too small. The interval width is unequal. The first class interval does not begin at 0. One interval is an open class.
The interval width is unequal.
Which of the following is a type of graphical display used to summarize quantitative, continuous data? histogram frequency polygon ogive all of the above
all of the above
A researcher records the number of children at a local school from single-, divorced-, and married-parent homes. This frequency data would be best displayed as a bar chart frequency polygon histogram ogive
bar chart
Which of the following is a type of graphical display used to summarize qualitative, discrete data? bar chart pie chart histogram both A and B
both A and B
Ungrouped data can be distributed as intervals categories upper and lower boundaries all of the above
categories
The three steps for constructing a simple frequency distribution are find the observed range, find the interval width, and construct the frequency distribution find the real range, count the scores, and construct the frequency distribution find the real range, find the interval width, and construct the frequency distribution all of the above
find the real range, find the interval width, and construct the frequency distribution
Which of the following requires the calculation of a real range? frequency distributions for categorical frequency distributions for ungrouped data frequency distributions for grouped data frequency distributions that do not use real data
frequency distributions for grouped data
A ________ is plotted at the midpoint of each interval, whereas a ________ is plotted at the upper boundary of each interval. histogram; bar chart frequency polygon; histogram frequency polygon; ogive histogram; frequency polygon
frequency polygon; ogive
A researcher summarizes a set of frequency data into five intervals. This is an example of a frequency distribution for ungrouped data grouped data inferential statistics population parameters
grouped data
A graphical display for grouped frequency distributions with continuous data is called a histogram bar chart pie chart scatter gram
histogram
A researcher measures the time (in seconds) that it takes children to complete a basic reading skills task. What type of graphical display would be most appropriate for summarizing the frequency of children falling into different intervals of time? histogram bar chart scatter gram all of the above
histogram
A researcher measures the weight (in ounces) of newborn infants in the month of March. What type of graphical display would be most appropriate for summarizing the frequency of infants falling into different intervals of weight? histogram bar chart scatter gram all of the above
histogram
The range of scores in each interval of a grouped frequency distribution is called the simple frequency interval width real range grouped data
interval width
Which graphical display lists percentages and not original scores histogram frequency polygon ogive all of the above
ogive
A percentile is also called a: score range distribution percentile point
percentile point
A cumulative percentage summary that indicates the percentage of scores at or below a given value is called a relative percentage relative frequency percentile rank cumulative frequency
percentile rank
Bar charts are a lot like histograms, except the bars displayed in the graph do not touch the bar chart summarizes quantitative data the bar chart summarizes continuous data all of the above
the bars displayed in the graph do not touch
What is the corresponding percentile of a percentile point the score the frequency the percentile rank always 100%
the percentile rank
A student scores in the 80th percentile on an exam. What does this mean in comparison to all other students? the student scored higher than 80% of all others who took the exam the student scored worse than 80% of all others who took the exam Of all those who took the exam, only 80% of them completed it the student would score the same grade on the exam 80% of the time
the student scored higher than 80% of all others who took the exam
A percentile point is the value of a score on a measurement scale below which a specified percentage of scores in a distribution fall a summary display that distributes the sum of percentages across a series of intervals an interval with no defined upper or lower boundary the range of values contained in each interval of a grouped frequency distribution
the value of a score on a measurement scale below which a specified percentage of scores in a distribution fall
Which characteristic of a histogram implies that it summaries continuous data? the data are plotted on the y-axis the vertical bars touch at the upper boundary of each interval the height of the vertical bars are not restricted the x-axis lists data on a nominal scale of measurement
the vertical bars touch at the upper boundary of each interval