Sample Size (6 LV each one is linked to another one)
Posted: Mon May 27, 2013 4:46 pm
Dear all,
I need to calculate my sample size for smartPLS. I have 6 LV (formative) and each one is linked to another LV (this would be the 7th)called "performance" (It might be reflective, I have drawn it like formative, though). There are no other links between the 6 LV. I would like to include a moderating effect, I guess I could divide the sample in 2 (pionner businesses and followers), run the PLS twice and see if the results are significantly different. I wanna see which LV has the greater impact in Performance for each group (pionners and Followers), which one the less impact...
But continuing with the simple size, I guess I have these options:
1) I have read that I could use POWER Analysis:
How many arrows arrive in each LV?
Choose the biggest number
Use this number as number of predictors in the multiple regression procedure in the G*Power to have the sample size
I have the program but don´t not well how it Works, with a power of 0,8, and an effect size of 0,15 (see cohen 92 table 1 for regressions), I´m not sure which tests do I need. Does it depend on my hiphotesys? For example for a t test it says I need only a sample of 43
2) 10 (or 5) TIMES RULE
Considering that no LV has more than 6 indicators, In my case it would mean the maxiumn number of arrows pointing a LV, i.e., 6 x 10= 60 minimun, isn´t it?
3) Cohen 92 --> in table 2 --> 6 regressions, medium effect, alpha 0,05--> sample of 97
DOES IT LOOK RIGHT? WHICH ONE SHOULD I USE?
(thank you very much in advance)
I need to calculate my sample size for smartPLS. I have 6 LV (formative) and each one is linked to another LV (this would be the 7th)called "performance" (It might be reflective, I have drawn it like formative, though). There are no other links between the 6 LV. I would like to include a moderating effect, I guess I could divide the sample in 2 (pionner businesses and followers), run the PLS twice and see if the results are significantly different. I wanna see which LV has the greater impact in Performance for each group (pionners and Followers), which one the less impact...
But continuing with the simple size, I guess I have these options:
1) I have read that I could use POWER Analysis:
How many arrows arrive in each LV?
Choose the biggest number
Use this number as number of predictors in the multiple regression procedure in the G*Power to have the sample size
I have the program but don´t not well how it Works, with a power of 0,8, and an effect size of 0,15 (see cohen 92 table 1 for regressions), I´m not sure which tests do I need. Does it depend on my hiphotesys? For example for a t test it says I need only a sample of 43
2) 10 (or 5) TIMES RULE
Considering that no LV has more than 6 indicators, In my case it would mean the maxiumn number of arrows pointing a LV, i.e., 6 x 10= 60 minimun, isn´t it?
3) Cohen 92 --> in table 2 --> 6 regressions, medium effect, alpha 0,05--> sample of 97
DOES IT LOOK RIGHT? WHICH ONE SHOULD I USE?
(thank you very much in advance)