(urgent) Sample Size

 PLS Junior User
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(urgent) Sample Size
Hi All,
Please advise me how to determine the appropriate sample size for running 2x2 factorial design by using PLS.
Kind Regard
Please advise me how to determine the appropriate sample size for running 2x2 factorial design by using PLS.
Kind Regard
 Diogenes
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Hi,
1000 or 5000 is recommended to the bootstrap procedure.
To the 2x2 factorial design I thought:
1) ANOVA to compare 4 groups (mean) = 180 cases [alpha = 5%, power = 80%, effect size = medium = 0.25]
2) Multigroup comparison (two independent path coefficients) = 356 cases [alpha = 5%, power = 80%, effect size = medium = 0.3]
See (Cohen, 1977) and use G*Power 3 (Faul, Erdfelder, Lang, & Buchner, 2007), it is free.
Cohen, J. (1977). Statistical power analysis for the behavioral sciences (Revised.). New York: Academic Press.
Faul, F., Erdfelder, E., Lang, A.G., & Buchner, A. (2007). G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior research methods, 39(2), 17591.
Best regards,
Bido
1000 or 5000 is recommended to the bootstrap procedure.
To the 2x2 factorial design I thought:
1) ANOVA to compare 4 groups (mean) = 180 cases [alpha = 5%, power = 80%, effect size = medium = 0.25]
2) Multigroup comparison (two independent path coefficients) = 356 cases [alpha = 5%, power = 80%, effect size = medium = 0.3]
See (Cohen, 1977) and use G*Power 3 (Faul, Erdfelder, Lang, & Buchner, 2007), it is free.
Cohen, J. (1977). Statistical power analysis for the behavioral sciences (Revised.). New York: Academic Press.
Faul, F., Erdfelder, E., Lang, A.G., & Buchner, A. (2007). G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior research methods, 39(2), 17591.
Best regards,
Bido
Halo Pak Anugrah,
Maybe you can try this:
Chin (1998) the sample required for PLS can be determined in the following ways: 1) the construct with the largest number of formative indicators or 2) the dependent latent variable with the largest number of relationship. The sample size required would be 5 to 10 times of either 1) or 2) whichever is higher
Semoga membantu...
Salam,
Maybe you can try this:
Chin (1998) the sample required for PLS can be determined in the following ways: 1) the construct with the largest number of formative indicators or 2) the dependent latent variable with the largest number of relationship. The sample size required would be 5 to 10 times of either 1) or 2) whichever is higher
Semoga membantu...
Salam,
 Diogenes
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Hi
The best way is using power analysis:
1) How many arrows arrive in each LV?
2) Choose the biggest number
3) Use this number as number of predictors in the multiple regression procedure in the G*Power to have the sample size.
Software G*Power 3 available at
http://www.psycho.uniduesseldorf.de/ab ... p/gpower3/
Best regards,
Bido
The best way is using power analysis:
1) How many arrows arrive in each LV?
2) Choose the biggest number
3) Use this number as number of predictors in the multiple regression procedure in the G*Power to have the sample size.
Software G*Power 3 available at
http://www.psycho.uniduesseldorf.de/ab ... p/gpower3/
Best regards,
Bido
Thank you for reply my question Pak Hussein and Mr Bido,
I owned a maximum of 7 LVs, will that mean my sample size is 70?
Can a sample size be smaller that the total number of cases?
(cases=91)
If i use G*Power3, i find 2 types.
There are 2 linear multiple regression
1) Fixed model, R2 deviation from zero (I have 138 sample sizes)
2) Fixed model, R2 increase (I have 107 sample sizes)
Which one should i use?
Is that ok from that results? or should be above 1000?
NB:
My model is hierarchical component model (repeated indicator approach)
Kind Regard
I owned a maximum of 7 LVs, will that mean my sample size is 70?
Can a sample size be smaller that the total number of cases?
(cases=91)
If i use G*Power3, i find 2 types.
There are 2 linear multiple regression
1) Fixed model, R2 deviation from zero (I have 138 sample sizes)
2) Fixed model, R2 increase (I have 107 sample sizes)
Which one should i use?
Is that ok from that results? or should be above 1000?
NB:
My model is hierarchical component model (repeated indicator approach)
Kind Regard
 Diogenes
 PLS SuperExpert
 Posts: 905
 Joined: Sat Oct 15, 2005 5:13 pm
 Real name and title:
 Location: São Paulo  BRAZIL
 Contact:
Hi,
1) Yes.
2) 0.8 is the minimum value recommended by Hair Jr. et al., but it depends of the field of research, in fact the default value of the G*Power is .95.
3) G*Power gives us the effect size (f2), and we need to compute the R2, see:
FAUL, F.; ERDFELDER, E.; LANG, A.G.; BUCHNER, A. G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior research methods, v. 39, n. 2, p. 17591, 2007.
f2 = R2/(1 – R2) [Faul et al., 2007, p.181]
R2 = f2/(1 + f2)
Best regards,
Bido
1) Yes.
2) 0.8 is the minimum value recommended by Hair Jr. et al., but it depends of the field of research, in fact the default value of the G*Power is .95.
3) G*Power gives us the effect size (f2), and we need to compute the R2, see:
FAUL, F.; ERDFELDER, E.; LANG, A.G.; BUCHNER, A. G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior research methods, v. 39, n. 2, p. 17591, 2007.
f2 = R2/(1 – R2) [Faul et al., 2007, p.181]
R2 = f2/(1 + f2)
Best regards,
Bido
i have 8 construct. for loyalty construct there are 4 direct predictor, s for using the mentioned software.
i can go to the
test> correlation and regression> linear multiple R2 zero
and for estimating the sample size
how i can acquire the effect size?
as you said
power=0.8
alpha=0.05
number of predictor is 4
but what about effect size?[/img][/list]
i can go to the
test> correlation and regression> linear multiple R2 zero
and for estimating the sample size
how i can acquire the effect size?
as you said
power=0.8
alpha=0.05
number of predictor is 4
but what about effect size?[/img][/list]
value of f2 in Gpower
is it true for my sample size 85? i dont know which vaue insert in effect size box?. for powe i insert 0.8. for alpha 0.05, and because 4 paths arrived ate loyalty which is the maximum i set 4 for number of predictor
but i dont know about number of f2? coul you please help me calculate sample size with Gpower?
Thank you
Nazila Babakhani
but i dont know about number of f2? coul you please help me calculate sample size with Gpower?
Thank you
Nazila Babakhani
 Diogenes
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With “small effects” your sample will be larger, and more sensible, it will detect small effects as significant.
Usually, to collect data is a problem (cost, time..) and we use the “medium effect”.
Remembering that with small samples we could finish with a model where nothing is significant.
Best regards,
Bido
Usually, to collect data is a problem (cost, time..) and we use the “medium effect”.
Remembering that with small samples we could finish with a model where nothing is significant.
Best regards,
Bido