Question 1

Sample size is not one of the likely determinants of statistical significance.

Accepted Answer

Sample size is actually one of the determinants of statistical significance. As sample size increases, the likelihood of finding a statistically significant result also increases.

Question 2

Phi coefficient is for examining the relationship between two dichotomous variables when the data are drawn from independent data and just like the Spearman rank correlation coefficient, the higher the score the stronger is the relationship between the two variables.

Accepted Answer

This statement accurately describes the Phi coefficient.

Question 3

The McNemar test is useful for the examination of the relationship between two nominal variables when the data are related.

Accepted Answer

The McNemar test is specifically used to analyze data when two nominal variables are related, making it useful in determining if there is a significant difference in the frequency of occurrence between the two variables. Therefore, the statement is true.

Question 4

A negative sign in front of the phi coefficient value in the output generated from SPSS is meaningless because you cannot have a positive or negative relationship between two nominal variables as this type of variable puts people into categories that have no order.

Accepted Answer

Nominal variables do not have a directional relationship, so a negative sign in front of the phi coefficient is meaningless.

Question 5

You cannot report the difference in proportions as your phi coefficient because it is only a quick-and-dirty estimate to be used before you actually calculate the real value.

Accepted Answer

The phi coefficient is a measure of association for two binary variables, providing a value between -1 and 1 that indicates the strength and direction of the association. It is not simply the difference in proportions, which would not account for the distribution of outcomes across the categories in the same way or provide a standardized measure of association.

Question 6

The binomial test could be used with the posttest only data when you have a threshold proportion for comparison.

Accepted Answer

The binomial test can be used to compare a proportion in a sample to a known threshold proportion, which is exactly what is needed in posttest-only data. Therefore, the statement is true.

Question 7

Chi square is an appropriate test when analyzing data from small samples.

Accepted Answer

Chi square test is generally applicable to larger-sized samples (at least 5 expected counts per cell). When the sample size is small, it can lead to inaccurate analysis and interpretation of results. In such cases, alternative tests like Fisher's exact test or Yates' correction can be employed.

Question 8

The contingency coefficient is used when one or more of your two nominal variables have more than two categories.

Accepted Answer

The contingency coefficient is used in contingency table analysis to assess the strength of association between two nominal variables where one or both variables have more than two categories.

Question 9

Practical significance is determined by the application of statistical tests.

Accepted Answer

Practical significance refers to the real-world importance or relevance of a statistical finding, not just whether the result is statistically significant. It considers the effect size and whether the findings have meaningful implications in practical scenarios, beyond just statistical tests.

Question 10

The expected frequency is the frequency for a given cell that would represent a failure to find statistical significance.

Accepted Answer

The expected frequency is the frequency that would be expected if there were no difference between the groups being compared. If the observed frequency is significantly different from the expected frequency, then this is evidence of a statistically significant difference between the groups.

Question 11

Explain the importance of the need to observe the expected frequencies in the cells when you compute a chi square test.

Accepted Answer

The answer of Explain the importance of the need to...

Question 12

When you compute chi square, the importance of expected frequencies and the logic behind it is evident in the method of calculating the expected frequencies for the cells. Please explain this process.

Accepted Answer

The answer of When you compute chi square, the importance...

Question 13

The phi coefficient does not calculate numerical order of the variables. Please explain.

Accepted Answer

The answer of The phi coefficient does not calculate numerical...

Question 14

Explain the process of using the Binomial test to compare the categories of a dichotomous variable.

Accepted Answer

The answer of Explain the process of using the Binomial...

Quiz 9: A Synopsis of Selected Statistical Tests for Examining Nominal Data