Section 1-2 Ex. 26
Surgery vs. Splints – A study compared surgery and splinting for subjects suffering from carpal tunnel syndrome. It was found that among 73 patients treated with surgery, there was a 92% success rate. Among 83 patients treated with splints, there was a 72% success rate. Calculations using these results showed that if there really is no difference in success rates between surgery and splints, then there is about a 1 in 1000 chance of getting success rates like the one obtained in this study.
a. Should we conclude that surgery is better than splints for the treatment of carpal tunnel syndrome? It would be unfair to make such a conclusion. There are pieces of data ...view middle of the document...
Section 1-4 Ex. 18
Bad Question – The author surveyed students with this request: “Enter your height in inches.” Identify two major problems with this request.
a. Problem 1: There is no stated goal for the study.
b. Problem 2: How large is the study?
Section 1-5 Ex. 8
Testing Echinacea – A study of the effectiveness of Echinacea involved 707 cases of upper respiratory tract infections. Children with 337 of the infections were given Echinacea, and children with 370 of the infections were given placebos.
* This study was an experiment. The group was divided into two sub-groups, one being given a treatment (the Echinacea) and the other group given a placebo.
Section 1-5 Ex. 18
Curriculum Planning – In a study of college programs, 820 students are randomly selected from those majoring in communications, 1463 students are randomly selected from those majoring in business, and 760 students are randomly selected from those majoring in history.
* The selection of students for this study is more indicative of Cluster sampling. We do not know exactly how many students are in each program, but of those selected in each group ALL will be used for the study.
Section 2-2 Ex. 12
Comparing Relative Frequencies – Construct one table (similar to Table 2-8 on page 57) that includes relative frequencies based on the frequency distributions from Exercises 7 and 8, then compare the weights of discarded metal and plastic. Do those weights appear to be the same or are they substantially different?
Weights (lb) of Discarded Metal | Frequency | Weights (lb) of Discarded Plastic | Frequency |
0.00-0.99 | 5 - 4.95 | 0.00-0.99 | 14 - 13.86 |
1.00-1.99 | 26 - 26/51.74 | 1.00-1.99 | 20 - 20/39.8 |
2.00-2.99 | 15 - 30/44.85 | 2.00-2.99 | 21 - 42/62.79 |
3.00-3.99 | 12 - 36/47.88 | 3.00-3.99 | 4 - 12/47.88 |
4.00-4.99 | 4 - 16/19.96 | 4.00-4.99 | 2 - 8/9.98 |
Total Metal: 112.95/169.38 | Total Plastic: 100.86/180.3 | 5.00-5.99 | 1 - 5/5.99 |
The weights are relatively close with...