SOLUTIONS MANUAL - BASIC BUSINESS STATISTICS: CONCEPTS AND APPLICA...

SOLUTIONS MANUAL

FOR

PAUL ILLICHGAIL ILLICH

BASIC BUSINESS STATISTICS:

CONCEPTS AND APPLICATIONS

FOURTEENTH EDITION

Mark L. Berenson David M. Levine Kathryn A. Szabat David F. Stephan (Download Link at the end of this File) 1 / 4

Copyright ©2019 Pearson Education, Inc.39

CHAPTER 1

1.1 (a) The type of beverage sold yields categorical or “qualitative” responses.(b) The type of beverage sold yields distinct categories in which no ordering is implied.

1.2 Three sizes of U.S. businesses are classified into distinct categories—small, medium, and large— in which order is implied.

1.3 (a) The time it takes to download a video from the Internet is a continuous numerical or “quantitative” variable because time can have any value from 0 to any reasonable unit of time.(b) The download time is a ratio scaled variable because the true zero point in the measurement is zero units of time.

1.4 (a) The number of cellphones is a numerical variable that is discrete because the outcome is a count. It is ratio scaled because it has a true zero point.(b) Monthly data usage is a numerical variable that is continuous because any value within a range of values can occur. It is ratio scaled because it has a true zero point.(c) Number of text messages exchanged per month is a numerical variable that is discrete because the outcome is a count. It is ratio scaled because it has a true zero point.(d) Voice usage per month is a numerical variable that is continuous because any value within a range of values can occur. It is ratio scaled because it has a true zero point.(e) Whether a cellphone is used for email is a categorical variable because the answer can be only yes or no. This also makes it a nominal-scaled variable.

1.5 (a) numerical, continuous, ratio scale (b) numerical, discrete, ratio scale (c) categorical, nominal scale (d) categorical, nominal scale

1.6 (a) Categorical, nominal scale.(b) Numerical, continuous, ratio scale.(c) Categorical, nominal scale.(d) Numerical, discrete, ratio scale.(e) Categorical, nominal scale.

1.7 (a) numerical, continuous, ratio scale * (b) categorical, nominal scale (c) categorical, nominal scale (d) numerical, discrete, ratio scale *Some researchers consider money as a discrete numerical variable because it can be “counted.”

1.8 (a) numerical, continuous, ratio scale * (b) numerical, discrete, ratio scale (c) numerical, continuous, ratio scale * (d) categorical, nominal *Some researchers consider money as a discrete numerical variable because it can be “counted.” 2 / 4

40 Chapter 1: Defining and Collecting Data

Copyright ©2019 Pearson Education, Inc.

1.9 (a) Income may be considered discrete if we “count” our money. It may be considered continuous if we “measure” our money; we are only limited by the way a country's monetary system treats its currency.(b) The first format is preferred because the responses represent data measured on a higher scale.

1.10 The underlying variable, ability of the students, may be continuous, but the measuring device, the test, does not have enough precision to distinguish between the two students.

1.11 (a) The population is “all working women from the metropolitan area.” A systematic or random sample could be taken of women from the metropolitan area. The director might wish to collect both numerical and categorical data.(b) Three categorical questions might be occupation, marital status, type of clothing.Numerical questions might be age, average monthly hours shopping for clothing, income.

1.12 The answer depends on the chosen data set.

1.13 The answer depends on the specific story.

1.14 The answer depends on the specific story.

1.15 The transportation engineers and planners should use primary data collected through an observational study of the driving characteristics of drivers over the course of a month.

1.16 The information presented there is based mainly on a mixture of data distributed by an organization and data collected by ongoing business activities.

1.17 (a) 001 (b) 040 (c) 902

1.18 Sample without replacement: Read from left to right in 3-digit sequences and continue unfinished sequences from end of row to beginning of next row.

Row 05: 338 505 855 551 438 855 077 186 579 488 767 833 170

Rows 05–06: 897

Row 06: 340 033 648 847 204 334 639 193 639 411 095 924

Rows 06–07: 707

Row 07: 054 329 776 100 871 007 255 980 646 886 823 920 461

Row 08: 893 829 380 900 796 959 453 410 181 277 660 908 887

Rows 08–09: 237

Row 09: 818 721 426 714 050 785 223 801 670 353 362 449

Rows 09–10: 406

Note: All sequences above 902 and duplicates are discarded.

1.19 (a) Row 29: 12 47 83 76 22 99 65 93 10 65 83 61 36 98 89 58 86 92 71 Note: All sequences above 93 and all repeating sequences are discarded. 3 / 4

Solutions to End-of-Section and Chapter Review Problems 41 Copyright ©2019 Pearson Education, Inc.

1.19 (b) Row 29: 12 47 83 76 22 99 65 93 10 65 83 61 36 98 89 58 86 cont. Note: All sequences above 93 are discarded. Elements 65 and 83 are repeated.

1.20 A simple random sample would be less practical for personal interviews because of travel costs (unless interviewees are paid to attend a central interviewing location).

1.21 This is a probability sample because the selection is based on chance. It is not a simple random sample because A is more likely to be selected than B or C.

1.22 Here all members of the population are equally likely to be selected and the sample selection mechanism is based on chance. But not every sample of size 2 has the same chance of being selected. For example the sample “B and C” is impossible.

1.23 (a) Since a complete roster of full-time students exists, a simple random sample of 200 students could be taken. If student satisfaction with the quality of campus life randomly fluctuates across the student body, a systematic 1-in-20 sample could also be taken from the population frame. If student satisfaction with the quality of life may differ by gender and by experience/class level, a stratified sample using eight strata, female freshmen through female seniors and male freshmen through male seniors, could be selected. If student satisfaction with the quality of life is thought to fluctuate as much within clusters as between them, a cluster sample could be taken.(b) A simple random sample is one of the simplest to select. The population frame is the registrar’s file of 4,000 student names.(c) A systematic sample is easier to select by hand from the registrar’s records than a simple random sample, since an initial person at random is selected and then every 20th person thereafter would be sampled. The systematic sample would have the additional benefit that the alphabetic distribution of sampled students’ names would be more comparable to the alphabetic distribution of student names in the campus population.(d) If rosters by gender and class designations are readily available, a stratified sample should be taken. Since student satisfaction with the quality of life may indeed differ by gender and class level, the use of a stratified sampling design will not only ensure all strata are represented in the sample, it will also generate a more representative sample and produce estimates of the population parameter that have greater precision.(e) If all 4,000 full-time students reside in one of 10 on-campus residence halls which fully integrate students by gender and by class, a cluster sample should be taken. A cluster could be defined as an entire residence hall, and the students of a single randomly selected residence hall could be sampled. Since each dormitory has 400 students, a systematic sample of 200 students can then be selected from the chosen cluster of 400 students. Alternately, a cluster could be defined as a floor of one of the 10 dormitories.Suppose there are four floors in each dormitory with 100 students on each floor. Two floors could be randomly sampled to produce the required 200 student sample. Selection of an entire dormitory may make distribution and collection of the survey easier to accomplish. In contrast, if there is some variable other than gender or class that differs across dormitories, sampling by floor may produce a more representative sample.

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