Ask Power - Recent questions and answers in Report bugs/errors

Answered: Error Message

Wed, 05 Aug 2026 23:56:48 +0000

This seemed to be related to a package update. It should have been fixed. Please let us know if it doesn't.

Answered: Error for output of skewness and kurtosis calculation

Thu, 21 May 2026 13:09:36 +0000

Thank you for your feedback. This seemed to be related to an update of package. We believe it has been fixed. Please try again and let us know if it still doesn't work. Thanks.

Answered: An error occured. Please check your input or contact us with the code c5e82b37570d75c49c6a748c12ddb959.

Thu, 21 May 2026 13:07:21 +0000

Thank you for your feedback. This seemed to be related to an update of package. We believe it has been fixed. Please try again and let us know if it still doesn't work. Thanks.

Answered: Trouble uploading data to effect size calculator

Wed, 25 Feb 2026 02:26:32 +0000

Anna, I am literally going through the exact same thing right now and it’s driving me up the wall. My anxiety is through the roof. Honestly, whenever I get this stressed out and things start breaking, I just have to walk away before I smash my monitor.

I usually end up just zoning out on this Telegram channel. They post the craziest videos - it’s the only thing that actually takes my mind off the stress. If you need a distraction while you wait for a fix, definitely check it out. Stay sane, y'all.

Answered: No calculation for mediation analysis models (moderate mediation)

Sat, 20 Sep 2025 01:06:47 +0000

The analysis was based on Monte Carlo simulation. So it will take a while to run to show the results in general.

Answered: Model 15 Power calculation no ouput

Fri, 31 May 2024 05:27:05 +0000

Hi there, thanks for reporting this bug. We've fixed this bug and model 15 should now give an output similar to the other models.

Answered: An encountered error when checking the results of the diagram based power analysis

Sat, 28 May 2022 15:57:40 +0000

The error seemed to be because that you didn't put the labels on the paths. To add a label to a path, double click the path or select it and then click the "T" icon.

Answered: Poisson power analysis

Wed, 09 Feb 2022 16:06:07 +0000

We have fixed the integration issue but it will take some time to push it to CRAN. If you need to use it now, you can use the following. Thanks.

library(WebPower)
source("https://webpower.psychstat.org/R/poisson.R")
wp.poisson(n = 40, exp0 = 0.15, exp1 = 3, alpha = 0.05, power = NULL, family = "normal", parameter = c(0, 1))

Using your example, the output is below

Power for Poisson regression
n power alpha exp0 exp1 beta0 beta1
40 0.9534119 0.05 0.15 3 -1.89712 1.098612
50 0.9825010 0.05 0.15 3 -1.89712 1.098612
60 0.9937320 0.05 0.15 3 -1.89712 1.098612
70 0.9978398 0.05 0.15 3 -1.89712 1.098612
80 0.9992791 0.05 0.15 3 -1.89712 1.098612
90 0.9997659 0.05 0.15 3 -1.89712 1.098612
100 0.9999257 0.05 0.15 3 -1.89712 1.098612
URL: http://psychstat.org/poisson

Answered: How can I fix the negative beta value in moderation analysis?

Fri, 07 Jan 2022 02:33:14 +0000

This is not really related to power analysis. But to answer your question, the result showed that TLS was actually a moderator here. The coefficient could be positive, negative or even 0. You don't have to get a positive coefficient to conclude the moderation effect.

Answered: Problems with wp.crt2arm

Mon, 03 Jan 2022 20:30:17 +0000

It worked fine on my computer, see the output. I am using WebPower version 0.5.2.

> wp.crt2arm(f=0.6,n=30,J=NULL, icc=.2,power=.8)
Cluster randomized trials with 2 arms
J n f icc power alpha
21.86552 30 0.6 0.2 0.8 0.05
NOTE: n is the number of subjects per cluster.
URL: http://psychstat.org/crt2arm

Answered: multivariate skewness and kurtosis online calculation excel file cant be open

Thu, 17 May 2018 03:24:22 +0000

There was an error with our server and it should have been fixed. But let us know if there is still a problem. Thanks.

Answered: A link is provided for a pdf of the power curve, even if the pdf is empty.

Thu, 05 May 2016 15:18:28 +0000

Thank you for the feedback. Could you provide an example here so that we can identify the problem? You could either provide the link to your power analysis with problem or let us know the power calculator and the parameters you used.