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Error Message

Wed, 05 Aug 2026 22:56:31 +0000

I attempted to run an a priori sample size calculation for Hayes Process Model 15 and received the following error message:

day=20260805&base=28f59c9ba8e3dcea2d1b41e94fd0f15c

Thanks for the simulation tool and assistance; it is much appreciated!

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

Thu, 21 May 2026 05:34:04 +0000

Error for output of skewness and kurtosis calculation

Wed, 13 May 2026 08:59:05 +0000

Output of skewness and kurtosis calculation

An error occured. Please check your input or contact us with the code 3f13029984c9c99e5f87ce81fc89bc8e.

No calculation for mediation analysis models (moderate mediation)

Mon, 26 Aug 2024 17:59:18 +0000

Hello! I am experiencing problems in the analysis of moderated mediation, both in ‘Model 7 ConditionalProcesses UsingJointSignificance’ and ‘Model 8 Conditional Processes Using Joint Significance’. Specifically, after entering the parameters, clicking on ‘calculate’ does not seem to happen, as if the command is not received. I have also tried changing browsers but the situation is the same. Thank you very much if you can help me!

Model 15 Power calculation no ouput

Thu, 23 May 2024 12:38:39 +0000

Hello, first of all I'm very thankful for your Power Analysis tool for moderated Mediations. For Model 14, everything seems to work just fine, there's an output after like a minute. But for Model 15 , there seems to be no output for like half an hour (and the caluclate button animation is resetting as there might should be an output). Is the compute for this model that heavy, or could this be a bug with Model 15? (or I might do something wrong)

Trouble uploading data to effect size calculator

Wed, 17 Apr 2024 15:21:55 +0000

Hi! I have tried uploading some data to WebPower to use the effect size calculator (https://webpower.psychstat.org/models/means05/effectsize.php), but have not been able to get my data uploaded (see section 4). The section for uploading doesn't specify which data format to use, but when I've uploaded repeated measures ANOVA data (3 columns, representing conditions, and 18 rows, representing participant ids) in .csv, .mat, and .txt format, none have worked.

The data appears to upload, but nothing happens when I click "Calculate". I've tried this function on both Safari and Chrome, in case there was a problem with the upload.

Thanks for any help on this front!

Best,

Anna

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

Sat, 28 May 2022 12:56:33 +0000

I report the following error. Please take care of it.

ERROR: An error has been found in your power analysis. Please send us the URL to your analysis day=20220528&base=ef6323e91eb8115984788fe8828ad4cb so that we can fix it. Thanks.

Poisson power analysis

Mon, 07 Feb 2022 21:23:33 +0000

Hi,

We're conducting a power analysis using wp.poisson to get the relative risk for different levels of a normally distributed predict (mean = 0, sd = 1). Our dependent variable is binary, but it was suggested that we use a poisson rather than logistic since the prevalence of the behavior we're observing is over 10% (22-40% has been observed in previous studies). The observed intercept in simulated data is -1.91, based on the 22% occurrence, so the IRR is 0.148. I used the relative risk for a small, medium and large effect as 1.22, 1.86, and 3.00, as suggested by Olivier et al (2017). I get an error when I try to run the medium and large effects of "non-finite function value." Here's my code:

medium <- wp.poisson(n = seq(40, 100, 10), exp0 = 0.15, exp1 = 1.86, alpha = 0.05, power = NULL, family = "normal", parameter = c(0, 1))

medium

Any suggestions for trouble shooting?

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

Thu, 06 Jan 2022 18:56:49 +0000

I am examining the moderating role of transformational leadership style (TLS) in the relationship between knowledge sharing (KS) and innovative work behavior (IWB). For this purpose, I have adopted a 25 items questioner, and I have received 250 responses.

in the SPSS 23 analysis, I run the "linear regression" to test the impact of moderating variables in the relationship between DV and IV. as a result in the "Coefficient" table shows a negative value of "-1.303" for "Beta Standard Coefficient" while the P-value is .000 "significant". (Photo attached in the below)

So, my question is: How can I get a positive value for "beta"? also which one of the variables needs to be corrected?

Thank you.

Problems with wp.crt2arm

Sat, 11 Sep 2021 20:12:47 +0000

Hello, I cannot calculate the number of clusters needed in a Cluster randomized trial, using wp.crt2arm in R. I don't know if it's a software problem. The message is as follows:

> wp.crt2arm(f=0.6,n=30,J=NULL, icc=.2,power=.8)

Error in nuniroot(function(J) eval(p.body) - power, ifelse(is.null(interval),: Please provide an interval with two values such as c(0,1).

multivariate skewness and kurtosis online calculation excel file cant be open

Thu, 17 May 2018 02:44:17 +0000

Hi,

I have used this webpower to test skewness and kurtosis using the online calculator before. However, since yesterday, my excel file uploaded, when click calculate, it shows 'can't open file'.

What is causing this? How can i measure my data normality?

Hope someone can assist me here. Thanks

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

Thu, 05 May 2016 14:59:47 +0000

When getting used to using the software, I tried to ask for a power curve while only one sample size value was provided (laterI figured out that the user has to provide multiple sample sizes for the plot). A link for a power curve pdf shows up in the results, however it will not open because the pdf has no pages.