Exam 3: Frequency Distributions

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 _________.

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

When constructing frequency distributions there must be 12 class intervals.

Define negatively skewed curve.

The following scores were obtained on a statistics exam. Construct a frequency distribution of grouped scores having approximately 12 intervals. Please show all work.

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

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

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

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

Sketch a cumulative frequency distribution for the following frequency distribution.

Assume the following are weights of a sample of junior high school students. Construct a stem and leaf diagram for the frequency distribution shown above.

The percentile rank of a score is defined as _________.

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 _________.

The professor teaching a large introductory class gives a final exam that has alternate forms, A, B, and C. A student taking the exam using Form B is upset because she claims that Form B is much harder than Forms A and C. Discuss how percentile point data might be useful to determine if the student is correct.

Plot a cumulative percentage distribution for the frequency distribution shown in the table below.

Given the data in the following table.

Define symmetrical curve.

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

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