Chapter 1 - What is Statistics?

Identify all of the following items which are qualitative variables?

The species of trees in a park. A person's favorite food type.

Which of the following variables is recorded at the interval level of measurement?

A man's shoe size

The two categories of statistical study are:

Descriptive statistics or Inferential statistics

What are two types of quantitative variables?

Discrete and Continuous

Explain the difference between discrete and continuous variable.

Discrete variables can assume only certain variables but continuous variables can assume any values within some range.

Which of the following represent statistical information? Select all that apply.

Lucky's Market sells a maximum of 240 kilograms of apples per month. On average there are 12.5 chocolate chips in a Chips Hello cookie. The median income in Wasau County is $40,578 per year.

What is descriptive statistics?

Methods of organizing, summarizing, and presenting data in an informative way.

What level of data is represented by the genres of music played by different radio stations?

Nominal

Which of the following are the four levels of measurement possible for data?

Nominal Ordinal Interval Ratio

Which of the following variables is recorded at the ration level of measurement?

Salaries of business school graduates.

You are shopping for a new MP3 music player such as the Apple iPod. The manufacturers advertise the number of music tracks that can be stored in the memory. Usually, the advertisers assume relatively short, popular songs to estimate the number of tracks that can be stored. You, however, like Broadway musical tunes and they are much longer. You would like to estimate how many Broadway tunes will fit on your MP3 player.

Sample

Which of the following are true with regard to the importance of studying statistics? Select all that apply.

Statistics is used to make personal and professional decisions. Data is everywhere, and statistics is needed to understand it. Statistical knowledge is need to understand the world and be conversant in your career.

Which of the three of the following are samples in the statistical sense?

Ten apples selected from a grocery store bin containing 100 apples. The GPA of every eighth person on the class roster. Six randomly chosen books from the library.

Identify which one of the following is a continuous quantitative variable.

The average weight of apples in a box at the market.

Which of the following are properties of ordinal level data?

The data can be ranked, rated or ordered.

Which of the following are not proper and ethical activities for a statistician in working with data? Select all that apply.

Use samples that represent only a desired part of the population. Report only those statistics that support his conclusions. Remove outliers that bias the data too far in one direction.

How has technology increased the need for statistical analysis?

Vast amounts of data are collected, and understanding it requires statistical knowledge.

Which of the following are examples of statistics? Select all that apply.

Yesterday's share price for Proctor and Gamble stock The median price of a house in Detroit The number of home runs in last year's World Series

Which of the following is not part of the science of statistics?

Choosing data that supports your conclusion

Which of the following are methods or techniques used in descriptive statistics? Select all that apply.

Constructing a frequency distribution. Constructing charts and graphs. Calculating summary measures like the average.

Which one of the following is a population in the statistical sense?

All of the automobiles sold in Canada in 2011.

For each of the following, determine whether the group is a sample or a population.

a. The participants in a study of a new cholesterol drug. Sample b. The drivers who received a speeding ticket in Kansas City last month. Population c. People on welfare in Cook County (Chicago), IL Population d. The 30 stocks that make up the Dow Jones Industrial Average. Sample

Statistics knowledge is necessary to successfully use business analytics.

True

Which of the following are discrete variables? Choose all that apply.

The number of customers using an ATM on a given day. The number of cars for sale on a used car lot.

Which of the following are examples of inferential statistics? Select all that apply.

Counting the blue candies in a package of M&M's as a way to estimate the proportion of blue candies in all packages. Estimating the average weight in a box of apples by measuring the weight of five apples.

Exits along interstate highways were formerly numbered successively from the western or southern board of the state. However, the Dept of Transportation has recently changed most of them to agree with the numbers on the mile markers along the highway. a. What level of measurement were data on the consecutive exit numbers? b. What level of measurement are data on the milepost numbers? c. The newer system provides information on the distance between exits.

a. Ordinal b. Ratio c. True

As a part of a research project, you need to report the average profit as a percentage of revenue for the #1-ranked corporation in the Fortune 500 for each of the last 10 years.

Population

Statistics 201 is a course taught at a university. Professor Rauch has taught nearly 1,500 students in the course over the past 5 years. You would like to know the average grade for the course based on all 1,500 students.

Population

You are looking forward to graduation and your first job as a salesperson for one of five large pharmaceutical corporations. Planning for your interviews, you will need to know about each company's mission, profitability, products, and markets.

Population

Explain the differences between qualitative and quantitative variables.

Qualitative data is none numerical, whereas quantitative data is numerical.

The Struthers Wells Corporation employs more than 10,000 white-collar workers in its sales offices and manufacturing facilities in the United States, Europe, and Asia. A sample of 300 U.S. workers revealed 120 would accept a transfer to a location outside the United States. On the basis of these findings, write a brief memo to Ms. Wanda Carter, Vice President of Human Services, regarding all white-collar workers in the firm and their willingness to relocate.

As a result of these sample findings, we can conclude that 40% of the white-collar workers would transfer outside the US

The nominal level of data describes what type of information?

Observations of qualitative variable that can only be classified and counted.

Which of the following is the best definition of a statistical sample?

A portion, or part of the population of interest.

Explain the difference between a sample and a population.

A sample is a subset taken from a population.

What is the level of measurement for each of the following variables?

a. Student IQ ratings. Interval b. Distance students travel to class. Ratio c. The jersey numbers of a sorority soccer team. Nominal d. A student's state of birth. Nominal e. A student's academic class-freshman, sophmore, etc Ordinal f. Number of hours student study per week Ratio

AVX Home Entertainment, Inc., recently began a "no-hassles" return policy. A sample of 500 customers who recently returned items showed 400 thought the policy was fair, 32 thought it took too long to complete the transaction, and the rest had no opinion. On the basis of this information, make an inference about customer reaction to the new policy. (Round your answers to 1 decimal place.)

Fair: 400/500=80.0% Too Long: 32/500=6.4% No Opinion: 500-400-32=68; 68/500=13.6% The above data suggest that majority of the customers