STATS Midterm Ch 2: Summarizing Data
What is the percentile point at the 90th percentile in the following distribution?
10
A researcher finds that 12% of participants make between three and five visits to a physician each year. What are the real limits for this interval?
2.5- 5.5
A researcher finds that 12 persons in a sample of 60 reported getting between 4 and 6 hr sleep per night. What is the relative percentage for this interval?
20%
The following is a simple frequency distribution table. If we convert this frequency distribution to relative percentages, which of the following gives the corresponding relative percentages in each interval listed from the top down?
20%, 13%, 17%, 33%, 17%
As a general rule, a simple frequency distribution should have between _______
5 and 20 intervals
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.
B is a bar chart; A is a histogram
State the problem with this simple frequency distribution
The class intervals overlap
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
Which of the following is a type of graphical display used to summarize quantitative, continuous data?
all of these - histogram - frequency polygon - ogive
A researcher distributes frequencies into the following classes: absent, tardy, and present. What type of data is distributed?
all of these - nominal data - qualitative data - ungrouped data
A simple frequency distribution
all of these - 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
A researcher records the number of children at a local school from single-, divorced-, and married-parent homes. These frequency data would be best displayed as a
bar chart
Ungrouped data can be distributed as
categories
The three steps for constructing a simple frequency distribution are
find the real range, find the interval width, and construct the frequency distribution
A _______ is plotted at the midpoint of each interval, whereas a ______ is plotted at the upper boundary of each individual
frequency polygon; ogive
A graphical display for grouped frequency distributions with continuous data is called a
histogram
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
The ______ is the percentage scores with values that fall below a specified score in a distribution
percentile rank
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
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
The following frequency distribution is an example of
ungrouped data
