/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q103E Thousands of students apply for ... [FREE SOLUTION] | 91影视

91影视

Thousands of students apply for admission to graduate schools in economics each year with the intention of obtaining a PhD. The Southern Economic Journal (April 2008) published a guide to graduate study in economics by ranking the PhD programs at 129 colleges and universities. Each program was evaluated according to the number of publications published by faculty teaching in the PhD program and by the quality of the publications. Data obtained from the Social Science Citation Index (SSCI) were used to calculate an overall productivity score for each PhD program. The mean and standard deviation of these 129 productivity scores were then used to compute a z-score for each economics program. Harvard University had the highest z-score 1z = 5.082 and, hence, was the top-ranked school; Howard University was ranked last because it had the lowest z-score 1z = -0.812. The data (z-scores) for all 129 economic programs are saved in the data file.

a. Interpret the z-score for Harvard University.

b. Interpret the z-score for Howard University.

c. The authors of the Southern Economic Journal article note that 鈥渙nly 44 of the 129 schools have positive z-scores, indicating that the distribution of overall productivity is skewed to the right.鈥 Do you agree?

Short Answer

Expert verified
  1. A total of 5.082 standard deviations are above the mean score.
  2. A total of 0.812 standard deviations are below the mean score.
  3. Yes.

Step by step solution

01

Interpretation of the z-score of Harvard University

The Southern Economic Journal has found the z-score associated with Harvard University is 5.082. This indicates that around 5.082 standard deviations are above the mean score of Harvard University.

02

Step 2:Interpretation of the z-score of Howard University

The Southern Economic Journal has found the z-score associated with Howard University is -0.812. This indicates that around 0.812 standard deviations are above the mean score of Harvard University.

03

Specification of skewness

The motion of the asseveration is correct that the distribution will be skewed to the right. It is because only a few schools have positive z-scores whereas a maximum number of schools have negative z-scores.

p+q=1q=1-p

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Salaries of bachelor鈥檚 degree graduates. PayScale, Inc., an online provider of global compensation data, conducts an annual salary survey of bachelor鈥檚 degree graduates. Three of the many variables measured by PayScale are the graduate鈥檚 current salary, mid-career salary, and the college or university where they obtained their degree. Descriptive statistics are provided for each of the over 400 colleges and universities that graduates attended. For example, graduates of the University of South Florida (USF) had a mean current salary of \(57,000, a median mid-career salary of \)48,000, and a mid-career 90th percentile salary of $131,000. Describe the salary distribution of USF bachelor鈥檚 degree graduates by interpreting each of these summary statistics.

Improving SAT scores.The National Education Longitudinal Survey (NELS) tracks a nationally representative sample of U.S. students from eighth grade through high school and college. Research published in Chance (Winter 2001) examined the Standardized Assessment Test (SAT) scores of 265 NELS students who paid a private tutor to help them improve their scores. The table summarizes the changes in both the 厂础罢鈥揗补迟丑ematics and 厂础罢鈥揤别谤产补濒 scores for these students.

厂础罢鈥揗补迟丑

厂础罢鈥揤别谤产补濒

Mean change in score

19

7

Standard deviation of score changes

65

49

a.Suppose one of the 265 students who paid a private tutor is selected at random. Give an interval that is likely to contain this student鈥檚 change in the 厂础罢鈥揗补迟丑 score.

b.Repeat part afor the 厂础罢鈥揤别谤产补濒 score.

c.Suppose the selected student increased his score on one of the SAT tests by 140 points. Which test, the SAT鈥 Math or 厂础罢鈥揤别谤产补濒, is the one most likely to have the 140-point increase? Explain.

Answer the following questions about the variability of data sets:

a.What is the primary disadvantage of using the range to compare the variability of data sets?

b.Describe the sample variance using words rather than a formula. Do the same with the population variance.

c.Can the variance of a data set ever be negative? Explain. Can the variance ever be smaller than the standard deviation? Explain.

Jamming attacks on wireless networks. Refer to the International Journal of Production Economics (Vol. 172, 2016) study of U.S. military jamming attacks on wireless networks used by terrorists, Exercise 1.16 (p. 50). Recall that 80 recent jamming attacks were classified according to network type (WLAN, WSN, or AHN) attacked and number of channels (single- or multi-channel) of the network. The results are summarized in the accompanying table.

Network Type/
Number of Channels

Number of
Jamming Attacks

WLAN / Single

31

WSN / Single

13

AHN / Single

8

WLAN / Multi

14

WSN / Multi

9

AHN / Multi

5

Total

80

a. Construct a Pareto diagram for the data. Interpret the results.

b. Construct a pie chart for network type only. Interpret the results.

Most valuable NFL teams.Refer to the Forbeslisting of the 2015 values of the 32 teams in the National Football League (NFL), Exercise 2.26 (p. 84). Construct a scatterplot to investigate the relationship between 2015 value (\( millions) and operating income (\) millions). Would you recommend that an NFL executive use operating income to predict a team鈥檚 current value? Explain.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.