For the chi-square tests in the analysis of categorical data, the rejection region 1.is always located in the lower tail of the distribution. 2.is alw

Answers (1)

2021-02-21

Step 1
Chi-Square test for independence:
In the test for independence, we test whether there is an association between the categorical variables.
Null hypothesis: There is no association between the two categorical variables.
Alternative hypothesis: There is an association between the two categorical variables.
Step 2
Here, to test the association between categorical variables, the critical region is always located in the upper tail of the distribution.
That is, Option 3 is correct.

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asked 2021-05-14

Consider the accompanying data on flexural strength (MPa) for concrete beams of a certain type.
\(\begin{array}{|c|c|}\hline 11.8 & 7.7 & 6.5 & 6 .8& 9.7 & 6.8 & 7.3 \\ \hline 7.9 & 9.7 & 8.7 & 8.1 & 8.5 & 6.3 & 7.0 \\ \hline 7.3 & 7.4 & 5.3 & 9.0 & 8.1 & 11.3 & 6.3 \\ \hline 7.2 & 7.7 & 7.8 & 11.6 & 10.7 & 7.0 \\ \hline \end{array}\)
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