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91Ó°ÊÓ

Children make choices Many new products introduced into the market are

targeted toward children. The choice behavior of children with regard to new products is of particular interest to companies that design marketing strategies for these products. As part of one study, randomly selected children in different age groups were compared on their ability to sort new products into the correct product category (milk or juice). Here are some of the data:

Researchers want to know if a greater proportion of 6- to 7-year-olds can sort correctly than 4- to5-year-olds.

a. State appropriate hypotheses for performing a significance test. Be sure to define the parameters of interest.

b. Check if the conditions for performing the test are met.

Short Answer

Expert verified

a. The hypothesis is H0:p1=p2and Ha:p1<p2

b. All conditions are met.

Step by step solution

01

Given Information

Researchers want to know if a greater population of 6-7years old can sort correctly than 4-5years old or not.

x1=10

x2=28

n1=50

n2=53

02

Appropriate hypothesis for performing significance test

Claim: Proportion is greater for 6-7years old.

Finding hypothesis:

As per the given data, hypothesis are:

H0:p1=p2

Ha:p1<p2

p1is proportion of 4-5years old who can sort correctly.

p2is proportion of6-7years old who can sort correctly.

03

Checkimg conditions

The conditions are:

Random: Children are independent random sample.

Independent: 50<10%of all 4-5old and 53<10%of all 6-7years old.

Normal: There are 10success and 40failures in first sample and 28success and 25failures which are greater than ten.

All conditions are satisfied. It is appropriate to use hypothesis test.

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Most popular questions from this chapter

According to sleep researchers, if you are between the ages of 12and 18years old, you need 9hours of sleep to function well. A simple random sample of 28students was chosen from a large high school, and these students were asked how much sleep they got the previous night. The mean of the responses was 7.9hours with a standard deviation of 2.1hours. If we are interested in whether students at this high school are getting too little sleep, which of the following represents the appropriate null and alternative hypotheses ?

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(c) role="math" localid="1654192807425" t=(6-5)-0360+240

(d) t=(6-5)-0360+240

(e)t=(6-5)-03260+2240


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