A researcher conducts a statistical test that reveals that the ...

[nelaaney]

A researcher conducts a statistical test that reveals that the four groups analyzed differed. The researcher wants to discover which one or ones of the four differed from the others. The researcher must then perform a post hoc analysis.
 
  What will this involve?
  a. Design of a second research study, using a new sample
  b. Descriptive statistics about the sample demographics
  c. Qualitative research generating new themes and ideas
  d. A second statistical test using the original data

Question 2

is the symbol for which of the following?
 
  a. Sample mean
  b. Population mean
  c. Population variance
  d. Sample variance

[SAUXC]

Answer to Question 1

ANS: D
Post hoc analyses are commonly performed in studies with more than two groups when the analysis indicates that the groups are significantly different but does not indicate which groups are different. A post hoc analysis must be performed to determine which of the three groups are significantly different. In other studies, the insights obtained through the planned analyses generate further questions that can be examined with the available data.

Answer to Question 2

ANS: A
Use of the terms statistic and parameter can be confusing because of the various populations referred to in statistical theory. A statistic (such as a mean, ) is a numerical value obtained from a sample. A parameter is a true (but unknown) numerical characteristic of a population. For example, is the population mean or arithmetic average. The mean of the sampling distribution (mean of samples' means) can also be shown to be equal to . Thus, a numerical value that is the mean ( ) of the sample is a statistic; a numerical value that is the mean of the population ( ) is a parameter.

[nelaaney]

Excellent

[strudel15]

Gracias!