INTRODUCTION TO STATISTICS & DATA ANALYS
6th Edition
ISBN: 9780357420447
Author: PECK
Publisher: CENGAGE L
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Chapter 9.1, Problem 4E
The authors of the paper “Influence of Biofeedback Weight Bearing Training in Sit to Stand to Sit and the Limits of Stability on Stroke Patients” (The Journal of Physical Therapy Science [2016]: 3011–2014) randomly selected two samples of patients admitted to the hospital after suffering a stroke. One sample was selected from patients who received biofeedback weight training for 8 weeks and the other sample was selected from patients who did not receive this training. At the end of 8 weeks, the time it took (in seconds) to stand from a sitting position and then to sit down again (called sit-stand-sit time) was measured for the people in each sample. Data consistent with summary quantities given in the paper are given below. For purposes of this exercise, you can assume that the samples are representative of the population of stroke patients who receive the biofeedback training and the population of stroke patients who do not receive this training.
Biofeedback Group
No Biofeedback Group
- a. Use the given data to estimate the
mean sit-stand-sit time for stroke patients who receive biofeedback training. - b. Use the given data to estimate the mean sit-stand-sit time for stroke patients who do not receive biofeedback training.
- c. Use the given information to estimate the standard deviation of sit-stand-sit times for stroke patients who receive biofeedback.
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Chapter 9 Solutions
INTRODUCTION TO STATISTICS & DATA ANALYS
Ch. 9.1 - Three different statistics are being considered...Ch. 9.1 - a. Why is an unbiased statistic generally...Ch. 9.1 - The report The 2016 Consumer Financial Literacy...Ch. 9.1 - The authors of the paper Influence of Biofeedback...Ch. 9.1 - Each person in a random sample of 20 students at a...Ch. 9.1 - Suppose that each of 935 smokers received a...Ch. 9.1 - Given below are the sodium contents (in mg) for...Ch. 9.1 - A random sample of n = 12 four-year-old red pine...Ch. 9.1 - A random sample of 10 houses heated with natural...Ch. 9.2 - Explain which would result in a wider large-sample...
Ch. 9.2 - Explain which would result in a wider large-sample...Ch. 9.2 - The formula used to calculate a large-sample...Ch. 9.2 - The use of the interval p(zcriticalvalue)p(1p)n...Ch. 9.2 - For each of the following combinations of sample...Ch. 9.2 - Discuss how each of the following factors affects...Ch. 9.2 - The USA TODAY Snapshot titled Social Media...Ch. 9.2 - Based on data from a survey of 1200 randomly...Ch. 9.2 - The report Parents, Teens and Digital Monitoring...Ch. 9.2 - If a hurricane was headed your way, would you...Ch. 9.2 - The USA TODAY Snapshot titled Big Bang Theory (USA...Ch. 9.2 - The article Most Dog Owners Take More Pictures of...Ch. 9.2 - The Princeton Review 2016 College Hopes and...Ch. 9.2 - The USA TODAY Snapshot titled Babys First Photo...Ch. 9.2 - The report Job Seeker Nation Study...Ch. 9.2 - USA TODAY reported that the proportion of...Ch. 9.2 - The USA TODAY Snapshot titled Have a Nice Trip...Ch. 9.2 - Business Insider reported that a study...Ch. 9.2 - In 2010, the National Football League adopted new...Ch. 9.2 - The article Most Americans Dont Understand the...Ch. 9.2 - The Gallup Organization conducts an annual survey...Ch. 9.2 - The article Hospitals Dispute Medtronic Data on...Ch. 9.2 - Based on survey of a representative sample of 1000...Ch. 9.2 - A discussion of digital ethics appears in the...Ch. 9.2 - In spite of the potential safety hazards, some...Ch. 9.2 - In 2010, the online security firm Symantec...Ch. 9.3 - Given a variable that has at distribution with the...Ch. 9.3 - The formula used to calculate a confidence...Ch. 9.3 - USA TODAY reported that the average amount of...Ch. 9.3 - Samples of two different models of cars were...Ch. 9.3 - USA TODAY reported that the average amount of...Ch. 9.3 - The paper The Effects of Adolescent Volunteer...Ch. 9.3 - Medical research has shown that repeated wrist...Ch. 9.3 - Students in a representative sample of 65...Ch. 9.3 - The paper referenced in the previous exercise also...Ch. 9.3 - Suppose that a random sample of 50 bottles of a...Ch. 9.3 - The authors of the paper Driving Performance While...Ch. 9.3 - The article The Association Between Television...Ch. 9.3 - The paper Patterns and Composition of Weight...Ch. 9.3 - Because of safety considerations, in May 2003 the...Ch. 9.3 - Example 9.3 gave the following airborne times (in...Ch. 9.3 - Consumer Reports gave the following mileage...Ch. 9.3 - Five students visiting the student health center...Ch. 9.3 - The Bureau of Alcohol, Tobacco, and Firearms...Ch. 9.3 - The formula described in this section for...Ch. 9.4 - The following quote is from the article Credit...Ch. 9.4 - Authors of the news release titled Major Gaps...Ch. 9.4 - The paper The Curious Promiscuity of Queen Honey...Ch. 9.5 - A survey on SodaHead...Ch. 9.5 - Prob. 59ECh. 9.5 - Prob. 60ECh. 9.5 - Prob. 61ECh. 9.5 - Prob. 62ECh. 9.5 - Prob. 63ECh. 9.5 - Prob. 64ECh. 9.5 - Prob. 65ECh. 9.6 - Prob. 66ECh. 9.6 - Prob. 67ECh. 9.6 - Teams in the National Football League (NFL) are...Ch. 9.6 - Prob. 69ECh. 9.6 - The Economist collects data each year on the price...Ch. 9.6 - Major League Baseball (MLB) includes two groups of...Ch. 9 - The article Write It by Hand to Make It Stick...Ch. 9 - Prob. 73CRCh. 9 - The report The 2016 Consumer Financial Literacy...Ch. 9 - The report The Politics of Climate (Pew Research...Ch. 9 - The report referenced in the previous exercise...Ch. 9 - Data from a survey of a representative sample was...Ch. 9 - A manufacturer of small appliances purchases...Ch. 9 - A manufacturer of college textbooks is interested...Ch. 9 - The confidence intervals presented in this chapter...Ch. 9 - Prob. 81CRCh. 9 - The interval from 2.33 to 1.75 captures an area of...
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