Busi Statistics

Identify whether the table given below is a frequency table or a frequency distribution. Age (Years) Frequency under 30 36 30 up to 40 18 40 up to 50 10 50 up to 60 24 50 and over 26 Frequency distribution

Explanation A frequency distribution involves quantitative data.

What type of variable is "pounds of popcorn" served at a movie theater? Continuous

Explanation "Pounds of popcorn" can assume any value within a range, and there are no gaps in the scale.

Speedy Swift is a package delivery service that serves the greater Atlanta, Georgia, metropolitan area. To maintain customer loyalty, one of Speedy Swift's performance objectives is on-time delivery. To monitor its performance, each delivery is measured on the following scale: early (package delivered before the promised time), on-time (package delivered within 15 minutes of the promised time), late (package delivered more than 15 minutes past the promised time), or lost (package never delivered). Speedy Swift's objective is to deliver 99% of all packages either early or on-time. Another objective is to never lose a package. Speedy collected the following data for last month's performance:

a. What kind of variable is delivery performance? What scale is used to measure delivery performance? Variable Qualitative Scale Ordinal b. Construct a frequency table for delivery performance for last month. Performance Frequency Early 21 On-time 67 Late 10 Lost 2 c. Construct a relative frequency table for delivery performance last month. (Round your answers to 2 decimal places.) Performance Frequency Early 0.21 On-time 0.67 Late 0.10 Lost 0.0 2 Explanation a.The scale is ordinal and the variable is qualitative. b.A frequency table groups qualitative data into mutually exclusive classes showing the number of observations in each class. c.Relative frequencies are computed by dividing each class frequency by the total of all observations.

Which of the following is an example of a continuous variable? Tons of concrete to complete a parking garage

Explanation A continuous variable assumes any value within a range. Numbers of students, zip codes, and rankings have "gaps" between the values and hence are not continuous.

In a marketing study, 100 consumers were asked to select the best digital music player from the iPod Touch, Sony Walkman, and the Zune HD. To summarize the consumer responses with a frequency table, how many classes would the frequency table have? Classes 3

Explanation A frequency table groups qualitative data into mutually exclusive classes. Thus, three classes are needed, one for each type of player.

Classify the following as a population or sample: a. All the people eligible to vote in the United States to elect the president for the next election. Population b. 10 students' marks recorded to estimate the average marks of the class. Sample

Explanation A population is the entire group which you are studying. A sample is a subset taken from a population.

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 40s% of the white-collar workers would transfer outside the U.S.

Explanation As a result of these sample findings, we can conclude that 120/300, or 40% of the white-collar workers would transfer outside the U.S.

A university wishes to conduct a student survey. In one of the questions, students are asked to mark their gender as either male or female. Gender is an example of the nominal scale.

Explanation Gender is a nominal variable because you can only classify the students into categories, and these categories have no natural order or ranking.

Explain the difference between a discrete and a continuous variable. Discrete variables can assume only certain values, but continuous variables can assume any values within some range.

Explanation No further explanation details are available for this problem.

Explain the difference between qualitative and quantitative variables. Qualitative data is not numerical, whereas quantitative data is numerical.

Explanation No further explanation details are available for this problem.

If Gallup, Harris, and other pollsters asked people to indicate their political party affiliations as Democrat, Republican, or Independent, the data gathered would be an example of which scale of measurement? Nominal

Explanation Political party affiliation is measured with a label or name and therefore is nominal. It is a categorization with no natural order and cannot be ranked or ordered.

The general process of gathering, organizing, summarizing, analyzing, and interpreting data is called statistics.

Explanation Statistics is the science of collecting, organizing, presenting, analyzing, and interpreting data to assist in making more effective decisions.

When TV advertisements report that "2 out of 3 dentists surveyed indicated they would recommend Brand X toothpaste to their patients," an informed consumer may question the conclusion because the advertisement does not include the total number of dentists surveyed.

Explanation The ad implies that most dentists would recommend the product. However, without knowing anything about how many dentists were selected, and how they were selected, it would be difficult to accept the results of the survey.

A poll solicits a large number of college undergraduates for information on the following variables: the name of their cell phone provider (AT&T, Verizon, and so on), the numbers of minutes used last month (200, 400, for example), and their satisfaction with the service (Terrible, Adequate, Excellent, and so forth). What is the level of measurement for each of these three variables? The cell phone provider Nominal The number of minutes used Ratio Satisfaction with the service Ordinal

Explanation The cell phone providers are different from each other but have no meaning other than identification. So they are nominal level of measurement. The minutes used has a significant zero point and the ratio of two numbers is meaningful. So they are ratio level of measurement. Satisfaction ratings are higher or lower than one another, but the differences between them are not the same. So the satisfaction ratings are ordinal level of measurement.

Ethical statisticians use honesty and integrity when summarizing, analyzing, and interpreting data.

Explanation The ethical practice of statistics requires that one uses honesty and integrity when summarizing, analyzing, and interpreting data. Reporting only data that matches your desired findings, withholding unfavorable information, or not being honest about limitations of your analysis or possible sources of error are not ethical practices.

AVX Home Entertainment Incorporated recently began a "no-hassles" return policy. A sample of 540 customers who recently returned items showed 360 thought the policy was fair, 150 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.) Customer Reaction Percent Fair 66.6% Too long 27.7% No opinion 5.7% The above data suggest that majority of the customers believe the policy is fair.

Explanation The obvious majority of customers (360/540, or 66.7%) believe the policy is fair with only 27.8% believing the policy is too cumbersome (150/540). On the strength of these findings, we anticipate all customers will feel the same and support the new policy.

The names of the positions in a corporation, such as chief operating officer or controller, are examples of what type of variable? Qualitative

Explanation The variable, job title, is qualitative.

Which of the following is true? No matter what your career, you need a knowledge of statistics to understand the world.

Explanation There are at least three reasons for studying statistics: 1) data are collected everywhere and require statistical knowledge to make the information useful, 2) statistical techniques are used to make professional and personal decisions, and 3) no matter what your career, you will need a knowledge of statistics to understand the world and to be conversant in your career. An understanding of statistics and statistical methods will help you make more effective personal and professional decisions.

The reported unemployment is 5.5% of the population. What level of measurement is used to measure unemployment? Ratio

Explanation Unemployment percentages have a true zero point (no unemployment), and the ratio between two values is meaningful. Consequently, this is ratio level data.

For the following situations, would you collect information using a sample or a population? a. A survey to rank the famous television shows in the United States. Sample b. A research project to find how many heart attack patients are admitted on January 1 to a famous hospital. Population c. A study to find the quality of matchsticks in a bundle of 100 matchboxes. Sample d. An evaluation of the creativity of the director of three films. Population

Explanation a. A sample is used because it is difficult to locate every viewer. b. A population is employed because the information is easy to find. c. A sample works because it is not easy to test every matchstick. d. A population is used because he directed only three films.

A set of data contains 53 observations. The minimum value is 42 and the maximum value is 129. The data are to be organized into a frequency distribution. a. How many classes would you suggest? Classes 6 b. What would you suggest as the lower limit of the first class? (Select the best value for the data.) Lower limit 40

Explanation a. For the number of classes (k) select the smallest integer such that 2 to the power of k is greater than the number of observations. 2^5 = 32, 2^6 = 64 suggests 6 classes. b.The classes must cover at least the distance from the lowest value (42) in the data up to the highest value (129). So the class interval (i) is at least i≥(129−42)/6=14.5. It is more convenient to round up to an interval of 15. Start first class a little below the lowest value (42) in the data. Forty appears to be ideal.

Exits along interstate highways were formerly numbered successively from the western or southern border of a state. However, the Department of Transportation 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? Ordinal b. What level of measurement are data on the milepost numbers? Ratio c. The newer system provided information on the distance between exits. True

Explanation a. One exit number is higher or lower than another, but the distance between them are not the same. So the exit number is ordinal level of measurement. b. The milepost number has a significant zero point and the ratio of two numbers is meaningful. So they are ratio level of measurement. c. The newer system provided more indirect information, namely the distance between exits.

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—that is, freshman, sophomore, junior, or senior. Ordinal f. Number of hours students study per week. Ratio

Explanation a. The difference between Student IQ ratings is a constant size. However, there is no meaningful zero point. So, they are interval level of measurement. b. The distance students travel to class has a significant zero point and the ratio between two distances is meaningful. So, they are ratio level of measurement. c. Jersey numbers are different from each other but have no meaning other than identification of particular players. So, they are nominal level of measurement. d. States of birth are different from each other but have no particular order to them. So, they are nominal level of measurement. e. One class rank is higher or lower than another, but the differences between the groups are not the same. So, class rank is ordinal level of measurement. f. The number of hours students study per week has a significant zero point and the ratio is between two numbers meaningful. So, they are ratio level of measurement.

Slate is a daily magazine on the Web. Its business activities can be described by a number of variables. What is the level of measurement for each of the following variables? a. The number of hits on their website on Saturday between 8:00 a.m. and 9:00 a.m. Ratio b. The departments, such as food and drink, politics, foreign policy, sports, etc. Nominal c. The number of weekly hits on the Sam's Club ad. Ratio d. The number of years each employee has been employed with Slate. Ratio

Explanation a. The number of hits on their web site on Saturday has a significant zero point and the ratio of two numbers is meaningful. So they are ratio level of measurement. b. The departments are different from each other but have no meaning other than identification. So they are nominal level of measurement. c. The number of weekly hits on the Sam's Club ad has a significant zero point and the ratio of two numbers is meaningful. So they are ratio level of measurement. d. The number of years each employee has been employed has a significant zero point and the ratio of two numbers is meaningful. So they are ratio level of measurement.

2,600 frequent business travelers were asked which Midwestern city they prefer: Indianapolis, Saint Louis, Chicago, or Milwaukee. 113 liked Indianapolis best, 455 liked Saint Louis, 1,395 liked Chicago, and the remainder preferred Milwaukee. Develop a frequency table and a relative frequency table to summarize this information. (Round the "Relative Frequency" to 3 decimal places.) City Frequency Relative Frequency Indianapolis 113 0.043 Saint Louis 455 0.175 Chicago 1,395 0.537 Milwaukee 637 0.245

Explanation Found by 1130 + 455 + 1,395 + 637 = 2,600 1130/2,600 455/2,600 1,395/2,600 637/2,600