Exam 1

1. Metainformation

   Tag	Value
   file	Inferential_Statistics_uu-Mediation-808-en_uu-Mediation-808-en
   name	uu-Mediation-808-en
   section	Inferential Statistics/Regression/Multiple linear regression/Mediation
   type	schoice
   solution	TRUE, FALSE, FALSE, FALSE
   Type	Case
   Language	English
   Level	Statistical Literacy

   Question

   In a study of influences on healing after major surgery, the following variables are involved: disease insight and IQ. In a mediator analysis examining whether the influence of IQ is through disease insight, the researcher finds the following relationships (expressed as regression coefficients):

   1. b = .64 of IQ -> healing. (2) b = .56 from IQ -> disease insight. (3) b = .55 of disease insight -> healing (where IQ is also included as a predictor in the model)

   The final analysis in this mediator analysis is a regression analysis with IQ and disease insight as predictors and healing as dependent variable….

   
   
   1. TRUE: Where you expect regression coefficient (1) to decrease.
   2. FALSE: Where you expect regression coefficient (2) to decrease.
   3. FALSE: Where you expect regression coefficient (3) to decrease.
   4. FALSE: Where you expect all three regression coefficients to decrease.
   
   

   Solution

   To test mediation, we examine the four steps (see question 12). The final step is to see if the relationship between IQ and healing is still significant when controlling for disease insight?

   When there is mediation, the relationship between IQ and healing will be weaker when disease insight is also included in the analysis. So you would expect regression coefficient (1) to decrease.