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I know that the T-Values have to be over 1,65 to be valid. Can anybody tell me about the minimum T-Values for the Path Coefficients?

Hi,

when we use t-values, and say that t-values are significant (t>1,65 for example), We are rejecting the hipotesis that correlation or path coefficient is equal to zero in the population (it´s significant).

Then you choose a significance level (90%, 95%, 99%, 99,9%) to have the critical t-value (minimum to be significant), or compute the significance (p-value) from the t-value presented in SmartPLS output.

Best regards

Bido

Use the following values
Two Tail
90% significance level--t value-1.645
95% significance level--t value-1.96
99% significance level--t value-2.57

One tail
90% significance level--t value-1.628
95% significance level--t value-1.645
99% significance level--t value-21.96

Sorry for one tail with 90% significance value the t-value is 1.28 not 1.628

Hi

I supposed that the t-statistic is actually z-statisitic as the values are the same as the Z table, am I right?

And should I use two tails or one tail?

Thanks

Since the bootstrap sizes are 100 or more, the values are actually z-values.

By default two tail values are better, although one tail values need smaller t-values to prove significance

viswadatta wrote:Since the bootstrap sizes are 100 or more, the values are actually z-values.

By default two tail values are better, although one tail values need smaller t-values to prove significance

Thanks a lot, I found literature said if the hypotheses is directional, one tail should use.

Can you give me an example of what is "one tail" and what is "two tails"?
thanx

I want to check my formative constructs (latent variables) in my model.

I know I have to check if the path coefficients from the indicators to the construct are significant. After bootstrapping, I got the t-values.

What should I do now?

I already calculated the p-values for each t-value. Have done it with the calculator from this site: http://danielsoper.com/statcalc3/calc.aspx?id=8

Example:
for the t-value of 2.525 the calculator says

Probability (one-tailed): 0.00586183
Probability (two-tailed): 0.01172366

How can I interpret this p-values? If I choose the two-tailed one, can I say its significant with a probability of error of 5% (because p<0,05), if I choosed my levels before as p<0,05, p<0,01 and p<0,001?

Another thing is, I am confused about if I should use a one-tailed t-test or the two-tailed t-test. In which case I have to use the one or the two tailed test?

And will be the whole procedere nearly the same if I wanna check the path coefficients of my inner model?

Please help!
Thanks!

We typical use the two-tailed test to check the weights and also the path coefficients.
cn

Do we need to determine the degree of freedom before deciding the t-value?, for example i have 101 observations, how do i determine the t-value significant level?

viswadatta wrote:Use the following values

One tail
90% significance level--t value-1.628
95% significance level--t value-1.645
99% significance level--t value-21.96

I think there may be a typing error for the t-value (one-tail) for 99% significance level. It is 2.326 and not 21.96. Please correct me if I'm wrong.

Thanks!

Sorry, there are more typing errors than one. Firstly, we typical use a two-tailed test. The critical t-values for a two-tail test are:

90% significance t-value = 1.64
95% significance t-value = 1.96
99% significance t-value = 2.58

For a one-tailed test the critical t-values are:

90% significance t-value = 1.28
95% significance t-value = 1.64
99% significance t-value = 1.96

I hope that helps!
Christian

droople wrote:

viswadatta wrote:
I found literature said if the hypotheses is directional, one tail should use.

Can you tell the literature you found?

Hi Namhyun,

You can find this in any statistical reference/textbook, not necessarily PLS reference.

Marwa