Mind on Statistics
Mind on Statistics
5th Edition
ISBN: 9781285463186
Author: Jessica M. Utts, Robert F. Heckard
Publisher: Brooks Cole
bartleby

Videos

Textbook Question
Chapter 1, Problem 1.16E

Suppose that an observational study showed that students who got at least 7 hours of sleep performed better on exams than students who got less than 7 hours of sleep. Which of the following are possible confounding variables, and which are not? Explain why in each case.

  1. Number of courses the student took that term.
  2. Weight of the student.
  3. Number of hours the student spent partying in a typical week.

Blurred answer

Chapter 1 Solutions

Mind on Statistics

Knowledge Booster
Statistics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.
Similar questions
  • Cholesterol Cholesterol in human blood is necessary, but too much can lead to health problems. There are three main types of cholesterol: HDL (high-density lipoproteins), LDL (low-density lipoproteins), and VLDL (very low-density lipoproteins). HDL is considered “good” cholesterol; LDL and VLDL are considered “bad” cholesterol. A standard fasting cholesterol blood test measures total cholesterol, HDL cholesterol, and triglycerides. These numbers are used to estimate LDL and VLDL, which are difficult to measure directly. Your doctor recommends that your combined LDL/VLDL cholesterol level be less than 130 milligrams per deciliter, your HDL cholesterol level be at least 60 milligrams per deciliter, and your total cholesterol level be no more than 200 milligrams per deciliter. (a) Write a system of linear inequalities for the recommended cholesterol levels. Let x represent the HDL cholesterol level, and let y represent the combined LDL VLDL cholesterol level. (b) Graph the system of inequalities from part (a). Label any vertices of the solution region. (c) Is the following set of cholesterol levels within the recommendations? Explain. LDL/VLDL: 120 milligrams per deciliter HDL: 90 milligrams per deciliter Total: 210 milligrams per deciliter (d) Give an example of cholesterol levels in which the LDL/VLDL cholesterol level is too high but the HDL cholesterol level is acceptable. (e) Another recommendation is that the ratio of total cholesterol to HDL cholesterol be less than 4 (that is, less than 4 to 1). Identify a point in the solution region from part (b) that meets this recommendation, and explain why it meets the recommendation.
  • Recommended textbooks for you
  • Glencoe Algebra 1, Student Edition, 9780079039897...
    Algebra
    ISBN:9780079039897
    Author:Carter
    Publisher:McGraw Hill
    Big Ideas Math A Bridge To Success Algebra 1: Stu...
    Algebra
    ISBN:9781680331141
    Author:HOUGHTON MIFFLIN HARCOURT
    Publisher:Houghton Mifflin Harcourt
    Holt Mcdougal Larson Pre-algebra: Student Edition...
    Algebra
    ISBN:9780547587776
    Author:HOLT MCDOUGAL
    Publisher:HOLT MCDOUGAL
  • College Algebra
    Algebra
    ISBN:9781337282291
    Author:Ron Larson
    Publisher:Cengage Learning
    Algebra: Structure And Method, Book 1
    Algebra
    ISBN:9780395977224
    Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole
    Publisher:McDougal Littell
  • Glencoe Algebra 1, Student Edition, 9780079039897...
    Algebra
    ISBN:9780079039897
    Author:Carter
    Publisher:McGraw Hill
    Big Ideas Math A Bridge To Success Algebra 1: Stu...
    Algebra
    ISBN:9781680331141
    Author:HOUGHTON MIFFLIN HARCOURT
    Publisher:Houghton Mifflin Harcourt
    Holt Mcdougal Larson Pre-algebra: Student Edition...
    Algebra
    ISBN:9780547587776
    Author:HOLT MCDOUGAL
    Publisher:HOLT MCDOUGAL
    College Algebra
    Algebra
    ISBN:9781337282291
    Author:Ron Larson
    Publisher:Cengage Learning
    Algebra: Structure And Method, Book 1
    Algebra
    ISBN:9780395977224
    Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole
    Publisher:McDougal Littell
    what is Research Design, Research Design Types, and Research Design Methods; Author: Educational Hub;https://www.youtube.com/watch?v=LpmGSioXxdo;License: Standard YouTube License, CC-BY