Textbook Notes (368,409)
BIOL499A (11)
Chapter 25

# Chapter 25final.pdf

8 Pages
69 Views

School
Department
Biology (Biological Sciences)
Course
BIOL499A
Professor
Blaine Mullins
Semester
Winter

Description
Chapter 25: Comparing Two Population Means – Paired Samples In this chapter, we will talk about:  The difference between independent and dependent samples,  Hypothesis tests for a matched pairs design,  Confidence intervals for   or a matched pairs design, 1 2 The blood pressure of five patients were recorded before and 30 minutes after receiving a drug. The results are given in the following table. Is the drug useful in reducing the blood pressure? Patients 1 2 3 4 5 Mean S.D. Before 146134110 126 157 134.6 18.105 After 140138110 116 144 129.6 13.822 Difference 6 -4 0 10 13 5.0 7.000 Inference about  1  2for a Matched Pairs Design: Let dyy 1 2 and d = Average of d-values s = Standard deviation of d-values. d So, we have  d 1 2 . An estimator of d is d and    ()  ()E d sd d n n To test the hypothesisH :    0 , the test statistic is: 0 1 2 d 0 TS  ~ t distribution, withdf  n 1,if H 0is true dn/ For H :0   , we rejectH ifTS  t* a d 1 2 0 * For H a d  1 2 , we rejectH 0if TS  t * * For H a d  1 2 , we reject H0if TS  t or TS  t A 100(1)% confidence interval ford 1 2 is given by: s dt * d n Example 25.1: Two computers often are compared by running a collection of different ``benchmark'' programs and recording the difference in CPU time required to complete the same program. Six benchmark programs, run on two computers, produced the following CPU times (in minutes): Benchmark Program 1 2 3 4 5 6 Computer 1 1.12 1.73 1.04 1.86 1.47 2.10 Computer 2 1.15 1.72 1.10 1.87 1.46 2.15 (a) Find a 99% confidence inte rval for the difference in mean CPU time required for the two computers to complete a job. Solution: (b) Does the data provide sufficient evidence to indicate that thmean CPU time required to complete a job is greater for computer 2 than for computer 1? Solution: Ex
More Less

Related notes for BIOL499A
Me

OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Join to view

OR

By registering, I agree to the Terms and Privacy Policies
Just a few more details

So we can recommend you notes for your school.