statistics_for accountguru

Data for Class project GRP#1

Blood Type	Pressure	Dosage	dosage square
3	-11	2	4	Note: In column A, 1=A, 2=B, 3=AB, and 4=O
4	-11	4	16
4	-16	2	4
3	2	8	64
3	8	10	4
1	-12	1	1
1	-3	0	4
1	-4	8	4
1	-9	0	0
3	5	9	4
1	-1	8	64
2	-10	3	4
1	-5	0	0
4	-11	7	4
1	-1	9	4
4	-4	1	1
1	-9	7	4
1	16	10	100
2	-9	0	4
3	5	9	81
2	-4	0	4
3	-4	0	4
1	-17	5	25
1	-4	0	4
1	-19	4	16
4	1	9	4
2	3	9	81
2	-12	5	4
3	-9	7	4
4	0	9	81
3	-8	1	4
2	-12	3	9
4	-11	6	4
1	-18	3	9
3	-8	7	4
3	-17	5	4
4	-15	3	9
2	-14	5	4
4	-13	1	1
3	-10	3	4
3	-5	7	49
2	-6	8	4
1	-6	8	4
3	-17	5	25
3	-13	3	4
4	-3	8	64
4	-4	0	4
2	2	0	0
1	-14	6	4
3	-5	0	4
3	-9	2	4
3	-6	0	4
2	-9	1	1
3	-11	7	4
3	-13	3	9
2	-5	0	4
4	-15	2	4
4	-12	1	1
1	-12	7	4
3	-5	0	0
2	8	10	4
1	-6	1	1
2	-17	4	4
1	9	10	4
1	-15	7	49
4	-14	6	4
4	-2	8	64
3	-6	0	4
2	-6	7	49
3	6	9	4
4	-8	8	4
3	-10	5	25
4	-7	7	4
4	11	10	100
2	-7	8	4
4	-17	2	4
1	-17	5	4
4	16	10	4
4	-9	1	1
2	-4	8	4
2	-14	2	4
2	8	10	4
2	-4	7	49
3	-10	2	4
2	-2	0	4
3	4	10	100
3	-4	8	4
2	-12	1	1
1	-13	4	4
4	-7	0	0
1	9	10	4
1	-4	0	4
4	-4	8	64
3	-1	0	4
2	-10	7	49
3	-7	1	4
3	-14	3	9
3	-14	4	4
1	-10	6	4
3	-14	6	36
2	-13	2	4
2	-8	7	49
1	-12	1	4
1	-18	4	16

Sheet2

Sample questions

You work for a pharmaceutical company that is currently testing a new antihypertensive (drug to reduce blood pressure). Your manager has recently asked you to do a quick preliminary analysis looking at the effectiveness of this drug. You have a sample of 104 patients who all had, prior to this test, a systolic blood pressure of approximately 175. These patients were given varying dosages of your drug, including some receiving a placebo. The quantity they were given is measured in mg/kg/day and is found in the column titled "dosage." After a two month treatment period, each patient had their systolic blood pressure retested; the difference between their initial blood pressure and their new blood pressure can be found in the colum "pressure." Lower (i.e. "more" negative) numbers in this column indicate a greater reduction in systolic blood pressure, and higher numbers imply that their systolic blood pressure actually increased. You also have data on patient blood type (A, B, AB, and O) in the column titled "blood type." Use this data to answer the following questions. Problem 4.1 comes from week 9 material, 4.2 comes from week 10 material, and 4.3 relates to week 11 material. Because this is due before week 11, question 4.3 is extra credit. Should you encounter any difficulties with these problems, the optional problems below are very similar to the questions in this problem set, and the answers to the optional questions can be found in the back of the textbook. You can also request that the tutor work extensively with you on the optional problems.

Research Question #1

The first issue your boss has asked you to address is whether or not there are differences in the effectiveness of the drug between the four different blood types. Use the 0.05 level of significance to: a) Perform a one-way ANOVA to look for differences in changes in blood pressure between blood types. (Use your book to solve this) b) Briefly summarize (in plain English) your procedures and the results of (a) Excel Tips: When using the Data Analysis ToolPak, Excel requires that your data be formatted differently for ANOVA than for regression. The data as downloaded is formatted correctly for regression analysis, so you will have to transform your data prior to estimating the ANOVA.

Research Question #2

In addition to looking at differences between blood types, your manager also wants to know the relationship between dosage and change in systolic blood pressure. Thus, the dosage is your independent variable and the change in blood pressure is your dependent variable. a)Construct a scatter plot of the two variables (note: the scatter plot should look non-linear. Still, do these questions and we'll address the non-linearity in 4.3) b)Estimate a simple linear regression between these two variables. c)Interpret the meaning of β0 and β1. d)Predict the mean blood pressure change associated with dosages of 0, 2.5, 5, 7.5, 10, and 12.5 Are these appropriate predictions? e)Comment briefly on the predictive power/statistical significance of your estimates.

Use The differents techniques that we used in that class to come up with some usefull way to abanlyze this data