Statistics and Probability Answers

The paper “Effect of long-term blood pressure control on salt sensitivity” [Journal of

Medicine (1997) 28:147–156] describes a study evaluating salt sensitivity (SENS) after a period of

antihypertensive treatment. Ten hypertensive patients (diastolic blood pressure between 90 and

115 mmHg) were studied after at least 18 months on antihypertensive treatment. SENS readings,

which were obtained before and after the patients were placed on an antihypertensive treatment,

are given here:

Patient 1 2 3 4 5 6 7 8 9 10

Before treatment 22.86 7.74 15.49 9.97 1.44 9.39 11.40 1.86
6.71 6.42

After treatment 6.11
4.02 8.04 3.29
0.77 6.99 10.19 2.09 11.40 10.70

a. Is there significant evidence that the mean SENS value decreased after the patient

received antihypertensive treatment?

b. Estimate the size of the change in the mean SENS value.

c. Do the conditions required for using the t procedures appear to be valid for these

data? Justify your answer

You collected data on incident of burglaries in 112 suburbs drawn from a number of major cities around the country. When plotting these on a normal (bell curve ) you find that of these 108 fall with in +2z and -2z of the mid point (mean) but 3 fall above 2z and one falls below 2z OUTLINE what your conclusion would be regarding the statistics drawn , with specific reference to the four suburbs that fall outside of 2z

1. Why is it important to identify first and develop your topic in conducting a research?

2. Why is it important to do a preliminary search for information before you start to conduct a social research?

3. What is the important of Proofreading in conducting a social research?

ACTIVITY 5. INTRODUCTION TO HYPOTHESIS TESTING

A. Illustrate the rejection region of the following by shading the appropriate region

• The rejection region of a two-tailed test
• The rejection region of a left-tailed test
• The rejection region of a right-tailed test

B. Determine the type of error being illustrated in each item.

1. Michael knows that it is wrong to cheat but he was caught cheating in his Math exam in order to pass.
2. Sheena knows that it is wrong not to return excess change given by the cashier and still did not return the excess money.
3. Maxine knows that in order to pass she needs to study hard but she did not review for the Third Quarter Examination
4. Ana witnessed a physical abuse and she knows that it should be reported but she did not report it to the authorities
5. Kim knows that it is wrong to smoke cigarette but he keeps on smoking.