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The type of household for the U.S. population and for a random sample of 411 hou

ID: 3350658 • Letter: T

Question

The type of household for the U.S. population and for a random sample of 411 households from a community in Montana are shown below.

Use a 5% level of significance to test the claim that the distribution of U.S. households fits the Dove Creek distribution.

(a) What is the level of significance?


State the null and alternate hypotheses.

H0: The distributions are different.
H1: The distributions are the same.

H0: The distributions are the same.
H1: The distributions are the same.     

H0: The distributions are the same.
H1: The distributions are different.

H0: The distributions are different.

H1: The distributions are different.


(b) Find the value of the chi-square statistic for the sample. (Round the expected frequencies to two decimal places. Round the test statistic to three decimal places.)


Are all the expected frequencies greater than 5?

Yes

No     


What sampling distribution will you use?

chi-square

normal     

Student's t

uniform

binomial


What are the degrees of freedom?


(c) Find or estimate the P-value of the sample test statistic. (Round your answer to three decimal places.)


(d) Based on your answers in parts (a) to (c), will you reject or fail to reject the null hypothesis that the population fits the specified distribution of categories?

Since the P-value > , we fail to reject the null hypothesis.

Since the P-value > , we reject the null hypothesis.     

Since the P-value , we reject the null hypothesis.

Since the P-value , we fail to reject the null hypothesis.


(e) Interpret your conclusion in the context of the application.

At the 5% level of significance, the evidence is sufficient to conclude that the community household distribution does not fit the general U.S. household distribution.

At the 5% level of significance, the evidence is insufficient to conclude that the community household distribution does not fit the general U.S. household distribution.     

Type of Household Percent of U.S.
Households
Observed Number
of Households in
the Community
Married with children 26%         102             Married, no children 29%         124             Single parent 9%         31             One person 25%         91             Other (e.g., roommates, siblings) 11%         63            

Explanation / Answer

(a) the level of significance=0.05

H0: The distributions are the same.
H1: The distributions are different.

(b) Find the value of the chi-square statistic for the sample.

Type of Household

% of U.S. Households

Observed Number of Households in Dove Creek

Married with children

26%

102

Married, no children

29%

124

Single parent

9%

31

One person

25%

91

Other (ie roommates, siblings)

11%

63

Type of Household

O

E

(O-E)^2

(O-E)^2/E

Married with children

102

411*0.26=106.86

23.6196

0.221033

Married, no children

124

411*0.29=119.19

23.1361

0.194111

Single parent

31

0.09*411=36.99

35.8801

0.969995

One person

91

411*0.25=102.75

138.0625

1.343674

Other

63

411*0.11=45.21

316.4841

7.000312

= 9.729125

Therefore,

the value of the chi-square statistic for the sample=9.729

Yes , all the expected frequencies greater than 5

chi-square sampling distribution will we use

the degrees of freedom = 5-1 = 4

(c) the P-value of the sample test statistic=0.045

The P-Value is 0.045. The result is significant at p < 0.05.

(d) Since the P-value , we reject the null hypothesis.

(e) Option first is correct.

At the 5% level of significance, the evidence is sufficient to conclude that the community household distribution does fit the general U.S. household distribution.

Type of Household

% of U.S. Households

Observed Number of Households in Dove Creek

Married with children

26%

102

Married, no children

29%

124

Single parent

9%

31

One person

25%

91

Other (ie roommates, siblings)

11%

63