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LOS a: Differentiate between descriptive statistics and inferential statistics, between a population and a sample, and among the types of measurement scales.

Which of the following statements regarding the terms population and sample is least accurate?

A)	A sample's characteristics are attributed to the population as a whole.

B)	A descriptive measure of a sample is called a statistic.

C)	A sample includes all members of a specified group.

A population includes all members of a specified group. A sample is a portion, or subset of the population of interest.

Which of the following statements about statistical concepts is least accurate?

A)	A frequency distribution is a tabular display of data summarized into a relatively small number of intervals.

B)	A sample contains all members of a specified group, but a population contains only a subset.

C)	A parameter is any descriptive measure of a population characteristic.

A population is defined as all members of a specified group, but a sample is a subset of a population.

A summary measure that is computed to describe a population characteristic from a sample is called a:

When sampling from a portion of the population, you compute a statistic to make inferences about the population.

Which one of the following alternatives best describes the primary use of inferential statistics? Inferential statistics are used to:

A)	make forecasts, estimates or judgments about a large set of data based on statistical characteristics of a smaller sample.

B)	summarize the important characteristics of a large data set based on statistical characteristics of a smaller sample.

C)	make forecasts based on large data sets.

Inferential statistics are used mainly to make forecasts, estimates or judgements about a large set of data based on statistical characteristics of a smaller set of data.

Which one of the following alternatives best describes the primary use of descriptive statistics? Descriptive statistics are used to:

A)	summarize important characteristics of large data sets.

B)	obtain data about the characteristics of any data set that can be used to assess the likelihood of the occurrence of future events.

C)	arrive at estimates regarding a large set of data regarding the statistical characteristics of a smaller sample.

Descriptive statistics are used mainly to summarize important characteristics of large data sets.

What is the main difference between descriptive statistics and inferential statistics? Descriptive statistics are:

A)	used to summarize data while inferential statistics are used to obtain precise information about a large data set.

B)	used to make forecasts about the likelihood of upcoming events while inferential statistics are used to summarize any data set.

C)	used to summarize a large data set while inferential statistics involves procedures used to make forecasts or judgments about a large data set by examining a smaller sample.

Descriptive statistics are used to summarize a large data set while inferential statistics are based on procedures used to make forecasts or judgments about a large data set by examining a smaller set of data.

Ratio scales are the strongest level of measurement; they quantify differences in the size of data and have a true zero point as the origin.

Fifty mutual funds are ranked according to performance. The five best performing funds are assigned the number 1, while the five worst performing funds are assigned the number 10. This is an example of a(n):

The ordinal scale of measurement categorizes and orders data with respect to some characteristic. In this example, the ordinal scale tells us that a fund ranked “1” performed better than a fund ranked “10,” but it does not tell us anything about the difference in performance.