Critical values for t

Frequently asked questions about PLS path modeling.
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planix
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Critical values for t

Post by planix »

Hi,

Can anyone tell me how to work out the critical values for t which is generated from bootstrapping? I want to report the statistical significance of path loadings but the published literature isn't really explicit on this. Some authors seem to use N-1 for degrees of freedom in relation to students-t distribution. My sample size was 85 so is df=84 the appropriate setting (Critical t for p<0.05 = 1.66)?

Thanks
Alistair Campbell, PhD
Senior Lecturer, Clinical Psychology
Associate Head of School
Director, JCU Psychology Clinic
James Cook University
AUSTRALIA
stefanbehrens
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Post by stefanbehrens »

Alistair,

your degrees of freedom (df) for the student distribution are not derived from your sample size, but rather from the number of bootstrap runs. E.g., if you ran the bootstrap with 500 runs, your df would be 499.

To determine the proper critical t-value, obviously you also need to consider whether you are running a one- or a two-sided test. The literature is generally not very explicit on this issue either.

Cheers,
Stefan
viswadatta
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critical t-values

Post by viswadatta »

I also have a question. Are t-values available only with bootstrap function, and not with general model?
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Diogenes
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Post by Diogenes »

For t-values see the aswers in viewtopic.php?t=151

and since normality isn´t a assumption in PLS, the t-values are computed from bootstrapping (the answer is yes).

Best Regards

Bido
viswadatta
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significance values

Post by viswadatta »

Should we take one sided or two sided significance values for the boot strap? The cut off t-values change for one sided and two sided significances.
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