Chapter 2 Practice Quiz - Frequency Distributions

A set of scores ranges from a high of X = 18 to a low of X = 5. If these scores were put in a grouped frequency distribution table with an interval width of 2 points, which of the following would be the top interval in the table?

18-19

A set of scores ranges from a high of X = 63 to a low of X = 28. If these scores were put in a grouped frequency distribution table, what would be the best choice for the interval width?

5 points

What is ΣX? X 3 2 1

6

For the following grouped frequency distribution table of exam scores, how many students had scores higher than X = 54? X f 60-64 3 55-59 4 50-54 5 45-49 2 40-44 1

7

For the following data, N = _____. X f 4 2 3 3 2 1 1 2

8.

For the following grouped frequency distribution table of exam scores, what is the lowest score on the exam? X f 90-99 3 80-89 1 70-79 2 60-69 3 50-59 4

Cannot be determined

Which statement below is correct regarding a grouped frequency distribution table?

The ∑x cannot be determined.

A researcher surveys a sample of n = 200 college students and asks each person to identify their favorite movie. Which kind of graph should be used to present these results?

bar graph

Which type(s) of frequency distribution graph(s) should be used for data that come from a nominal scale of measurement?

bar graphs

Which type(s) of frequency distribution graph(s) should be used for data that come from an interval scale of measurement?

histograms or polygons

What is the shape of a frequency distribution where scores tend to pile up on the right side, tail tapering off to the left.

negatively skewed

Using the frequency distribution table below, what is the proportion of individuals that scored a 4? X f 6 4 5 3 4 7 3 2 2 2 1 2

.35

For the following grouped frequency distribution table of exam scores, how many students had scores lower than X = 75? X f 95-99 6 90-94 3 85-89 4 80-84 5 75-79 2 70-74 1

1

For the following grouped frequency distribution table, what is the width of each class interval? X f 20-29 2 30-39 5 40-49 4 50-59 1

10

A set of scores ranges from a high of X = 45 to a low of X = 11. If these scores were placed in an appropriately designed grouped frequency distribution table, which of the following would be the bottom interval in the table?

10-14

For the following distribution of quiz scores, if a score of X = 4 or lower is a failing grade, how many individuals failed the quiz? X f 6 3 5 6 4 5 3 5 2 3 1 2

15

What is the total number of scores for the distribution shown in the following table? X f 4 7 3 5 2 4 1 2

18

For the following frequency distribution of quiz scores, how many individuals took the quiz? X f 5 6 4 5 3 5 2 3 1 2

21

In a grouped frequency distribution table, one interval is listed as 35-39. If the scores represent a continuous variable, what are the real limits for this interval?

34.5 and 39.5

A sample of n = 12 scores ranges from a high of X = 7 to a low of X = 4. If these scores are placed in a frequency distribution table, how many X values will be listed in the first column?

4

For the following distribution of quiz scores, how many individuals had a score of X = 4? X f 6 1 5 6 4 4 3 4 2 2 1 2

4

Which of the following is not an appropriate interval width to use when constructing a grouped frequency distribution table.

4 points

What is the percentile rank for a score of 4 in the frequency distribution table below? X f 6 4 5 5 4 1 3 3 2 6 1 1

55th

Which of the following statements pertaining to skewed and normal distributions is correct?

A skewed distribution tends to have one tail, and a normal distribution tends to have two tails.

Consider the distribution of exam scores for the first exam within a college course. If the set of exam scores forms a symmetrical distribution, what can be concluded about the students' scores?

About an equal number of students had relatively high and relatively low scores.

Bars that do not touch on the x axis. Used for nominal and ordinal data.

Bar Graphs

For the following grouped frequency distribution table, how many people had scores less than X = 14? X f 30-34 3 25-29 2 20-24 2 15-19 5 10-14 4 5-9 1

Cannot be determined

______________________is the spread of those scores based on the range of scores and the frequency of each.

Distribution

_____________________is the # of people with a particular score.

Frequency

If a set of exam scores forms a negatively skewed distribution, what can you likely conclude about the students' scores?

Most of the students had relatively high scores.

When would you use a grouped frequency table?

When you have a wide range of data.

If the following grouped frequency distribution table pertaining to a continuous variable were shown in a histogram, the width of the bar above the 15-19 interval would reach from _____ to _____. ​ X f 20-24 2 15-19 5 10-14 4 5-9 1

X = 14.5 to X = 19.5

In a frequency distribution graph, frequencies are presented on the _____ and the scores (categories) are listed on the _____.

Y axis; X axis.

A researcher collects a sample of n = 20 Introductory Psychology textbooks and records the number of pages in each book. The results are then placed in a grouped frequency distribution table using intervals of 0-99 pages, 100-199 pages, 200-299 pages, and so on. If the results were converted into a frequency distribution graph, which kind of graph(s) would be appropriate?

a histogram or polygon

A researcher surveys a sample of n = 10 adults and asks them to indicate their favorite day of the week. If the data were organized in a frequency distribution table, what would be included in the first column?

a list of days of the week

A researcher surveys a sample of n = 20 college students and asks each person to identify their favorite movie. If the data were organized in a frequency distribution table, what would be included in the last column?

a list of frequencies

After recording the final grade (A, B, C, D, F) for each individual in a class of N = 26 students, the professor would like to display the grade distribution in a frequency distribution graph. Which kind of graph should be used?

bar graph

For the following grouped frequency distribution table, how many people have scores greater than X = 45? X f 60-69 4 50-59 3 40-49 7 30-39 2

cannot be determined

Percentile ranks are closely tied to which of the following terms?

cumulative percentages

If a set of scores for a variable is displayed in a frequency distribution polygon, which scale of measurement was used to measure the variable?

interval or ratio

If a set of scores is displayed using a smooth curve, which scale of measurement was used to measure the scores?

interval or ratio

If a distribution of scores is shown in a bar graph, the scores were measured using a(n) _____ scale of measurement.

nominal or ordinal

In a frequency distribution graph with negative skew, scores with the highest frequencies are _____ of the distribution.

on the right side

The students in a psychology class seem to think that the midterm exam was very difficult. If they are correct, what is the most likely shape for the distribution of exam scores?

positively skewed

What is the shape of the distribution for the following set of data? Scores: 1, 1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 5

positively skewed

What is the shape of the frequency distribution for the following set of data regarding students' scores on a 10-item quiz? X f 9 1 8 1 7 3 6 6 5 6

positively skewed

Which term is used to describe the shape of a frequency distribution graph in which most scores pile up on the left-hand side of the graph and taper off to the right?

positively skewed

A biologist records the number and types of fish caught in a local lake during a 2- year period. The biologist reports that 7% of the fish caught during this period were trout, whereas 43% of the fish caught were bass. These reports of the number of trout and bass at this lake are examples of _____.

relative frequencies.

The normal distribution is an example of a _____.

smooth curve showing data from a population.