Racial Crossover. Refer to Exercise 11.108 and find and interpret a 95% confidence interval for the difference between the stroke incidences of white and African-American elderly.

Short Answer

Expert verified

There is 95%the interval for the difference between the proportion is(-0.029,0.015)

Step by step solution

01

Given Information

The given values are,

x1=529,n1=4989,x2=103,n2=906.

02

Explanation

The formula for p~1is given by,

p~1=x1n1

The formula for p~2is given by,

p~2=x2n2

The formula forz,is given by,

z=p~1-p~2p~p1-p~p1n1+1m2

The value of p~1is calculated as,

p~1=x1n1=5294989=0.106

The value of p~2is calculated as,

p~2=x2n2=103906=0.113

The critical value of Zfor two-tail test and 5%level of significance is 1.96.

The 95%confidence interval is.

p~1-p~2±za2p~11-p~1n1+p~11-p~1n2=(0.106-0.113)

±1.960.106(1-0.106)4989+0.113(1-0.113)906

=-0.007±0.022

Therefore, there is 95%interval for the difference between the proportion is (-0.029,0.015)

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Most popular questions from this chapter

In this Exercise, we have given the number of successes and the sample size for a simple random sample from a population. In each case,

a. use the one-proportion plus-four z-interval procedure to find the required confidence interval.

b. compare your result with the corresponding confidence interval found in Exercise 11.25-11.30, if finding such a confidence interval was appropriate.

role="math" localid="1651327118166" x=35,n=50,99%level

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