The University of Chicago’s General Social Survey (GSS) is the nation’s most important social science sample survey. For reasons known only to social scientists, the GSS regularly asks a random sample of people their astrological sign. Here are the counts of responses from a recent GSS:

12If births are spread uniformly across the year, we expect all 12 signs to be equally likely. Are these data inconsistent with that belief? Carry out an appropriate test to support your answer. If you find a significant result, perform a follow-up analysis

Short Answer

Expert verified

There is insufficient evidence to conclude that the data is consistent with the belief .

Step by step solution

01

Given information

Given the question, the General Social Survey (GSS) of the University of Chicago is the nation's most important social science sample survey. The GSS frequently asks a random sample of people their astrological sign for reasons only social scientists understand. The following are the response counts from a recent GSS:

If births are evenly distributed throughout the year, all 12 signs should be equally likely.

We must determine whether these data contradict that belief.

02

Explanation

The dataset is,

Count
321
360
367
374
383
402
392
329
331
354
376
355

The following formula can be used to compute the test statistic:

x2=(O-E)2E

The null and alternative hypotheses are as follows:

H0:p1=0.0833

H0:p2=0.0833

H0:p3=0.0833

H0:p4=0.0833

H0:p5=0.0833

H0:p6=0.0833

H0:p7=0.0833

H0:p8=0.0833

H0:p9=0.0833

H0:p10=0.0833

H0:p11=0.0833

H0:p12=0.0833

Ha:At least one of piis incorrect

03

Calculation for test statistic 

The test statistic is calculated as follows:

Observed ValueExpected value(O-E)
(O-E)2
(O-E)2E
321
362
-41
1681
4.46436
360
362
-2
4
0.011
367
362
6
25
0.0691
374
362
12
144
0.3978
383
362
21
441
1.2182
402
362
40
1600
4.4199
392
362
30
900
2.4862
329
362
-22
1089
3.0083
331
362
-31
961
2.6547
354
362
-8
64
0.1768
376
362
14
196
0.5414
355
362
-7
49
0.1354




localid="1653293158775" 𝚺=19.7624
04

Test statistic 

The following is the test statistic:

χ2=(O-E)2E=19.7624
The degree of freedom is determined as follows:

Degreeoffreedom=Numberofcategories-1=12-1=11

At 11degrees of freedom, the chi-square table p-value is 0.00054. The p-value is not statistically significant. The null hypothesis is discovered to be incorrect.

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