Statistics Chapter 2 Quiz

Which graphical display lists percentages and not original scores

ogive

The following frequency distribution is an example of

ungrouped data

As a general rule, a simple frequency distribution should have between

5 and 20 intervals

Ungrouped data can be distributed as

categories

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?

20%

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

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]

Fill in the missing values for A and B in this frequency distribution table:

A = 3.2, B = 13

State the type of graphical display for Graph A and Graph B. Refer to the Image.

B is a bar chart; A is a histogram.

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 unequal.

A ________ is plotted at the midpoint of each interval, whereas a ________ is plotted at the upper boundary of each interval.

frequency polygon; ogive

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]

A cumulative percentage summary that indicates the percentage of scores at or below a given value is called a

percentile rank

Grouped data are to ungrouped data as

quantitative is to qualitative

To determine the interval width, we divide the ________ by the number of intervals.

real range

To construct a pie chart, first distribute the data as

relative percentages

Bar charts are a lot like histograms, except

the bars displayed in the graph do not touch

What is the corresponding percentile of a percentile point

the percentile rank

Grouped data can be distributed

as a range of values with upper and lower boundaries into intervals [all of the above]

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

Which of the following is a type of graphical display used to summarize qualitative, discrete data?

bar chart pie chart

State the problem with this simple frequency distribution

The class intervals overlap

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?

2.5-5.5

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

The range of scores in each interval of a grouped frequency distribution is called the

interval width

The three steps for constructing a simple frequency distribution are

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 grouped data

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]

A researcher summarizes a set of frequency data into five intervals. This is an example of a frequency distribution for

groped data

A graphical display for grouped frequency distributions with continuous data is called a

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

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

Which of the following is a type of graphical display used to summarize quantitative, continuous data?

histogram frequency polygon ogive [all of the above]

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

A percentile point is

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 vertical bars touch at the upper boundary of each interval

A relative frequency distribution is appropriate when

there are large frequency counts in each interval

The sum of relative frequencies for each interval is _____

1.00

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.

20%, 13%, 17%, 33%, 17%

What is the percentile point at the 50th percentile for the following distribution?

30.5

What is the percentile point at the 80th percentile in the following distribution?

8

What is the percentile point at the 90th percentile in the following distribution?

9.5

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 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 top down

A percentile is

a percentile point

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

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]

Grouped data are distributed into ________, whereas ungrouped data are distributed into ________.

intervals; categories

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?

one interval is an open class

A percentile is also called a:

percentile point

The ________ is the percentage of scores with values that fall below a specified score in a distribution, is called the:

percentile rank