Bundle: Introduction to Statistics and Data Analysis, 5th + WebAssign Printed Access Card: Peck/Olsen/Devore. 5th Edition, Single-Term
5th Edition
ISBN: 9781305620711
Author: Roxy Peck, Chris Olsen, Jay L. Devore
Publisher: Cengage Learning
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Chapter 13, Problem 16CRE
Many people take ginkgo supplements advertised to improve memory. Are these over-the-counter supplements effective? In a study reported in the paper “Ginkgo for Memory Enhancement” (Journal of the American Medical Association [2002]: 835–840), elderly adults were assigned at random to either a treatment group or a control group. The 104 participants who were assigned to the treatment group took 40 mg of ginkgo three times a day for 6 weeks. The 115 participants assigned to the control group took a placebo pill three times a day for 6 weeks. At the end of 6 weeks, the Wechsler Memory Scale (a test of short-term memory) was administered. Higher scores indicate better memory
Based on these results, is there evidence that taking 40 mg of ginkgo three times a day is effective in increasing mean performance on the Wechsler Memory Scale? Test the relevant hypotheses using α = 0.05.
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Many people take ginkgo supplements advertised to improve memory. Are these over-the-counter supplements effective? In a study reported in the paper “Ginkgo for memory Enhancement” (Journal of the American Medical Association), elderly adults were assigned at random to either a treatment or a control group. The 104 participants who were assigned to the treatment group took 40 mg of ginkgo three times a day for six weeks. The 115 participants assigned to the control group took a placebo pill three times a day for six weeks. At the end of six weeks, the Wechsler Memory Scale (a test of short-term memory) was administered. Higher scores indicate better memory function. Summary values are given in the following table.
TABLE ATTACHED AS PICTURE
Based on these results, we want to find whether there is evidence that taking 40 mg of ginkgo three times a day is effective in increasing mean performance on the Wechsler Memory Scale.
A) Calculate the test statistic for the test above. (round test…
A particular paper described a study of children who were underweight or normal weight at age 2. Children in the sample were classified according to the number of sweet drinks consumed per day and whether or not the child was overweight one year after the study began. Is there evidence of an association between whether or not children are overweight after one
year and the number of sweet drinks consumed? Assume that it is reasonable to regard the sample of children in this study as representative of 2 to 3 years old children and then test the appropriate hypotheses using a .05 significance level. (Round your answer to two decimal places.)
Number of Sweet Overweight?
Drinks Consumed
per Day
Yes
No
22
930
1
73
2071
2
56
1681
3 or More
102
3389
x2 = |
P-value interval
Op< 0.001
O 0.001 s p < 0.01
O 0.01 sp < 0.05
O 0.05 sp < 0.10
Op2 0.10
There is --Select---
v to conclude that there is an association between whether or not children are overweight after one year and the number of sweet…
Chapter 13 Solutions
Bundle: Introduction to Statistics and Data Analysis, 5th + WebAssign Printed Access Card: Peck/Olsen/Devore. 5th Edition, Single-Term
Ch. 13.1 - Prob. 1ECh. 13.1 - The flow rate in a device used for air quality...Ch. 13.1 - The paper Predicting Yolk Height, Yolk Width,...Ch. 13.1 - Prob. 4ECh. 13.1 - Suppose that a simple linear regression model is...Ch. 13.1 - a. Explain the difference between the line y x...Ch. 13.1 - Prob. 7ECh. 13.1 - Hormone replacement therapy (HRT) is thought to...Ch. 13.1 - Prob. 9ECh. 13.1 - A simple linear regression model was used to...
Ch. 13.1 - Consider the accompanying data on x = Advertising...Ch. 13.2 - What is the difference between and b? What is the...Ch. 13.2 - The largest commercial fishing enterprise in the...Ch. 13.2 - Prob. 14ECh. 13.2 - Prob. 15ECh. 13.2 - Prob. 16ECh. 13.2 - An experiment to study the relationship between x...Ch. 13.2 - The paper The Effects of Split Keyboard Geometry...Ch. 13.2 - The authors of the paper Decreased Brain Volume in...Ch. 13.2 - Do taller adults make more money? The authors of...Ch. 13.2 - Researchers studying pleasant touch sensations...Ch. 13.2 - Prob. 22ECh. 13.2 - Prob. 23ECh. 13.2 - Consider the accompanying data on x = Research and...Ch. 13.2 - Prob. 25ECh. 13.2 - In anthropological studies, an important...Ch. 13.3 - The graphs accompanying this exercise are based on...Ch. 13.3 - Prob. 28ECh. 13.3 - Prob. 29ECh. 13.3 - The article Vital Dimensions in Volume Perception:...Ch. 13.3 - Prob. 31ECh. 13.3 - An investigation of the relationship between x =...Ch. 13.4 - Prob. 33ECh. 13.4 - Prob. 34ECh. 13.4 - Prob. 35ECh. 13.4 - Prob. 36ECh. 13.4 - A subset of data read from a graph that appeared...Ch. 13.4 - Prob. 38ECh. 13.4 - Prob. 39ECh. 13.4 - Prob. 40ECh. 13.4 - The shelf life of packaged food depends on many...Ch. 13.4 - For the cereal data of the previous exercise, the...Ch. 13.4 - The article Performance Test Conducted for a Gas...Ch. 13.5 - Prob. 44ECh. 13.5 - Prob. 45ECh. 13.5 - A sample of n = 353 college faculty members was...Ch. 13.5 - Prob. 47ECh. 13.5 - Prob. 48ECh. 13.5 - The accompanying summary quantities for x =...Ch. 13.5 - Prob. 50ECh. 13.5 - Prob. 51ECh. 13.6 - Prob. 52ECh. 13 - Prob. 53CRCh. 13 - Prob. 54CRCh. 13 - Prob. 55CRCh. 13 - The article Photocharge Effects in Dye Sensitized...Ch. 13 - Prob. 57CRCh. 13 - Prob. 58CRCh. 13 - Prob. 59CRCh. 13 - Prob. 60CRCh. 13 - Prob. 61CRCh. 13 - The article Improving Fermentation Productivity...Ch. 13 - Prob. 63CRCh. 13 - Prob. 64CRCh. 13 - Prob. 65CRCh. 13 - Prob. 1CRECh. 13 - Prob. 2CRECh. 13 - Prob. 3CRECh. 13 - Prob. 4CRECh. 13 - Prob. 5CRECh. 13 - The accompanying graphical display is similar to...Ch. 13 - Prob. 7CRECh. 13 - Prob. 8CRECh. 13 - Consider the following data on y = Number of songs...Ch. 13 - Many people take ginkgo supplements advertised to...Ch. 13 - Prob. 11CRECh. 13 - Prob. 12CRECh. 13 - Prob. 13CRECh. 13 - Prob. 14CRECh. 13 - The discharge of industrial wastewater into rivers...Ch. 13 - Many people take ginkgo supplements advertised to...Ch. 13 - It is hypothesized that when homing pigeons are...Ch. 13 - Prob. 18CRE
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