# multiple moderated regression steps

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## multiple moderated regression steps

 hi, ım studying moderated effects of percieved social support and justice world belief on relationship between stress coping strategies and depression level. ı haver never run this analysis before soi ı want to check my steps whether correct or not. first ı run regression in step 1 centered independent variables and centered moderators in step2 two way interactions instep 3 three way interactions as results ı found significiant two way and three way interactions. "It  ıs important after this" for example two way interactions; ı run 2 slopes that fit in with Winnifred's suggestion (http://www.docstoc.com/docs/21151269/Moderated-Multiple-Regression-v5 p.6) my criteria for significence was the centered indipendent vairable (that has significant interaction level) in Block 2--------- is this way is correct????? second to plot this slope ı used Dawson' s 2 way unstandardised excel spreadsheet (http://www.jeremydawson.co.uk/slopes.htm). In spreadsheet it is required to enter unstandardised regression coefficients of IV, moderator and interaction. ın which block the coefficients are true for entering IV and moderator co efficients????? ın 1 block (that include main effects) or in 2 block (that include interactions)????? one more question: In three way spreadshhet it is necessary to enter variance of IV*Moderator coefficient. ın matrıx which covariance block is correct to enter this value? should ı look at second covariance block or third covariance block. like this,for value of Covariance of IV*Mod1, IV*Mod2 coefficients which covariance block must be taken as correct??? thaks so much Note: excuse me for my English
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## Re: multiple moderated regression steps

 How does it help to center the variables?  What statistical principles are you using to fit your model and how are you ensuring statistical validity of inferential estimates?  Why do it in multiple steps?  Why use a mixture of software tools?  What is the utility of standardized regression coefficients? Frank stamkiral wrote hi, ım studying moderated effects of percieved social support and justice world belief on relationship between stress coping strategies and depression level. ı haver never run this analysis before soi ı want to check my steps whether correct or not. first ı run regression in step 1 centered independent variables and centered moderators in step2 two way interactions instep 3 three way interactions as results ı found significiant two way and three way interactions. "It  ıs important after this" for example two way interactions; ı run 2 slopes that fit in with Winnifred's suggestion (http://www.docstoc.com/docs/21151269/Moderated-Multiple-Regression-v5 p.6) my criteria for significence was the centered indipendent vairable (that has significant interaction level) in Block 2--------- is this way is correct????? second to plot this slope ı used Dawson' s 2 way unstandardised excel spreadsheet (http://www.jeremydawson.co.uk/slopes.htm). In spreadsheet it is required to enter unstandardised regression coefficients of IV, moderator and interaction. ın which block the coefficients are true for entering IV and moderator co efficients????? ın 1 block (that include main effects) or in 2 block (that include interactions)????? one more question: In three way spreadshhet it is necessary to enter variance of IV*Moderator coefficient. ın matrıx which covariance block is correct to enter this value? should ı look at second covariance block or third covariance block. like this,for value of Covariance of IV*Mod1, IV*Mod2 coefficients which covariance block must be taken as correct??? thaks so much Note: excuse me for my English Frank Harrell Department of Biostatistics, Vanderbilt University