Exam 1 for Business Statistics

The Union of Electrical Workers of America with 9,128 members polled 362 members about a new wage package that will be submitted to management. The population is the 362 members.

FALSE The 362 members are a sample or portion of the population of 9,128 union members.

There are four levels of measurement: qualitative, quantitative, discrete, and continuous.

FALSE The four levels of measurement are nominal, ordinal, interval, and ratio.

The mean deviation is the sum of the absolute differences between each value and the median.

FALSE The mean absolute deviation is the sum of the absolute differences between each value and the mean.

For a set of data arranged or sorted in numerical order, the value of the observation in the center is called the weighted mean.

FALSE The median is the value in the center of the data.

The order that runners finish in a race would be an example of continuous data.

FALSE The order that runners finish a race is an example of an ordinal level of measurement and is discrete data.

In a company, the standard deviation of the ages of female employees is 6 years and the standard deviation of the ages of male employees is 10 years. These statistics indicate that the dispersion of age is greater for females than for males.

FALSE The standard deviation of age for males is larger, indicating there is more dispersion among the males.

The variance is the mean of the sum of the squared deviations between each observation and the median.

FALSE The variance is the mean of the sum of the squared deviations between each observation and the mean.

For any distribution, there are an equal number of values above and below the mean.

FALSE There are an equal number of observations above and below the median.

If we select 100 persons from 25,000 registered voters and question them about candidates and issues, the 100 persons are referred to as the population.

FALSE The 100 people are a sample or portion of the population of 25,000 registered voters.

A store asks shoppers for their zip code to identify market areas. Zip codes are an example of ratio data.

FALSE While zip codes use numbers they are only labels. Therefore, they represent a nominal measurement scale.

The ordinal level of measurement is considered the "lowest" level of measurement.

FALSE The nominal scale is the "lowest" level of measurement.

To infer something about a population, we usually take a sample from the population.

TRUE

A population is a collection of all individuals, objects, or measurements of interest.

TRUE

According to Chebyshev's Theorem, 75% of the observations lie within plus and minus 2.00 average mean deviations.

FALSE 75% of the observations are within two standard deviations of the mean.

A listing of 100 family annual incomes is an example of statistics.

FALSE A listing of incomes is raw data. Statistics is used to organize, summarize, and present the data.

Extremely high or low scores affect the value of the median.

FALSE A median is the middle observation in a sorted list of data. The values do not have any effect on the median.

A set of ordinal-, interval-, or ratio-level data may only have one mode.

FALSE A set of observations may have more than one mode. For example, the following set of data has two modes, 3 and 7: 1, 2, 3, 3, 3, 4, 4, 5, 7, 7, 7, 10.

The terms descriptive statistics and inferential statistics can be used interchangeably.

FALSE Descriptive statistics are used to organize, summarize, and present data. Inferential statistics uses sample information to make inferences about a population.

Descriptive statistics are used to find out something about a population based on a sample.

FALSE Inferential statistics uses sample information to find out something about a population.

Categorizing voters as Democrats, Republicans, and Independents is an example of interval level measurement.

FALSE Political party is a label that corresponds to a nominal level of measurement.

A marketing research agency was hired to test a new DVD player. Consumers rated it outstanding, very good, fair, or poor. The level of measurement for this experiment is ordinal.

TRUE

A sample is a portion or part of the population of interest.

TRUE

A value that is typical or representative of the data is referred to as a measure of central location.

TRUE

According to the Empirical Rule, about 95% of the observations lie within plus and minus 2.00 standard deviations.

TRUE

An ordinal level of measurement implies some sort of ranking.

TRUE

Based on a sample of 3,000 people, the civilian unemployment rate in the United States was 5.5%. 5.5% is referred to as a statistic.

TRUE

Data measured on a nominal scale can only be classified into categories.

TRUE

For any data set, Chebyshev's Theorem estimates the proportion of observations that occurs within k standard deviations of the mean, where k is greater than 1.0.

TRUE

In a sample of 10 people, 3 persons earn $8 an hour, 6 earn $9 an hour, and 1 earns $12 an hour. The weighted mean hourly wage is $9.

TRUE

Statistics are used as a basis for making decisions.

TRUE

Statistics are used to report the summary results of market surveys.

TRUE

Statistics is defined as a body of techniques used to facilitate the collection, organization, presentation, analysis, and interpretation of information for the purpose of making better decisions.

TRUE

The CIA World Factbook cited these numbers for the United States: The birthrate is 14.14 births per 1,000 population. The average life expectancy for females is 80 years. Approximately 290 million persons reside in the United States. Each of these numbers is referred to as a statistic.

TRUE

The arithmetic mean is the sum of the quantitative observations divided by the total number of observations.

TRUE

The average number of passengers on commercial flights between Chicago and New York City is an example of a statistic.

TRUE

The branch of mathematics used to facilitate the collection, organization, presentation, analysis, and interpretation of numerical information is referred to as statistics.

TRUE

The mode is the value of the observation that appears most frequently.

TRUE

The number of children in a family is a discrete variable.

TRUE

The principal difference between the interval and ratio scale is that the ratio scale has a meaningful zero point.

TRUE

The standard deviation is the positive square root of the variance.

TRUE

The sum of the deviations from the mean for the set of numbers 4, 9, and 5 will equal zero.

TRUE

Variation describes the degree of dispersion in the data.

TRUE