1342 - Final Exam Review - Unit 1

A variable is a characteristic that changes or varies over time, and/or for different individuals or objects under consideration. An experimental unit is the individual or object on which a variable is measured.

• True

• False

Bar and pie charts are graphical techniques for qualitative data. Bar charts focus the attention on the frequency of the occurrences of the categories, and pie charts emphasize the percentage of occurrences of each category.

• True

• False

Twenty-five percent of a sample of 200 professional tennis players indicated that their parents did not play tennis. This is an example of descriptive statistics as opposed to inferential statistics.

• True

• False

Statistical inference is the process of making an estimate, prediction, or decision about a population based on sample data.

• True

• False

Descriptive statistics deals with methods of:

​

 a. organizing data

b. summarizing data

c. presenting data in a convenient and informative way

d. all of the above

e. only organizing and summarizing data

• A

• B

• C

• D

• E

The relative frequency of a class is computed by:

• dividing the frequency of the class by the number of classes

• dividing the frequency of the class by the class width

• dividing the frequency of the class by the total number of observations in the data set

• subtracting the lower limit of the the class from the upper limit and multiplying the differences by the number of classes

• adding the lower limit of the class to the upper limit and multiplying the sum by the number of classes

Which of the following is not the goal of descriptive statistics?

 a. summarizing data

b. displaying aspects of the collected data

c. reporting numerical findings

d. estimating characteristics of the population based on a sample

e. none of these

 

• A

• B

• C

• D

• E

You asked ten of your classmates about their weight. Based on this information, you stated that the average weight of all students in your university or college is 158 pounds. This is an example of:

• descriptive statistics

• statistical inference

• sample

• population

• sample and population

The sum of the frequencies for all classes will always equal:

• the number of classes

• the class width

• the total number of observations in the data set

• one

• the average

Two graphical techniques we usually use to present qualitative data are:

• bar chart & histogram

• histogram & pie chart

• bar chart & pie chart

• line chart & steam and leaf plot

• bar chart & line chart