WebPower WIKI

index - [Example data sets]

johnny (johnny@undisclosed.example.com) — 2026-10-11T01:01:23+00:00

WebPower Manual WebPower is a collection of tools for conducting statistical power analysis online. WebPower can be used by anyone for free. To use the software now, click here. For a short tutorial on how to use WebPower, click here. For the free online manual book (more than 30MB), please [click here]. To order a hard copy of the book, click the book cover below:

bass

johnny (johnny@undisclosed.example.com) — 2026-10-11T00:58:50+00:00

Bass-Ackward Factor Analysis Description The Bass-Ackward procedure explores hierarchical relationships among factor solutions with different numbers of factors. WebPower runs the analysis on the numeric variables in the uploaded data, determines the largest factor solution that meets its automatic stopping rule, and displays a diagram and the factor loadings.

index

johnny (johnny@undisclosed.example.com) — 2026-10-11T00:51:39+00:00

Tools * Univariate and multivariate skewness and kurtosis (Old version) * Normality evaluation of real data (New version) * Convert data among TXT, CSV, SAS, SPSS, STATA and Excel * Bass-Ackward Factor Analysis

a_new_app_to_convert_different_types_of_statistical_data - [Convert a file]

johnny (johnny@undisclosed.example.com) — 2026-10-07T15:50:17+00:00

A new app to convert different types of statistical data Use the Statistical Data Conversion app to convert a data file from one supported format to another. The maximum upload size is 20 MB. The app identifies the input format from the file extension.

data_conversion - [Convert a file]

johnny (johnny@undisclosed.example.com) — 2026-10-07T15:50:06+00:00

Data Conversion Use the Statistical Data Conversion app to convert a data file from one supported format to another. The maximum upload size is 20 MB. The app identifies the input format from the file extension. Supported formats Format Input Output

changelog

johnny (johnny@undisclosed.example.com) — 2026-09-30T16:25:04+00:00

Change Logs * Updated the jQuery from 1.9.1 to 4.0 * Updated the interface to mobile device friendly.

start - [Acknowledgement]

johnny (johnny@undisclosed.example.com) — 2026-08-23T14:22:10+00:00

Statistical Power Analysis Online WebPower is a collection of tools for conducting statistical power analysis online. WebPower can be used by anyone for free. To use the software now, click here. For a short tutorial on how to use WebPower, click here. For the online manual book (more than 30MB), please

service

johnny (johnny@undisclosed.example.com) — 2025-12-13T01:38:00+00:00

Statistical Consulting Service The WebPower development team provides consulting services, including statistical software support and assistance with experimental design and analysis to the research community. We provides assistance with experimental design and data analysis for all phases of research projects, including but not limited to:

hedge_s_g - [Hedges' g for independent two-sample design]

johnny (johnny@undisclosed.example.com) — 2025-04-27T18:21:07+00:00

Hedges' g for independent two-sample design ---------- In independent two-sample design, the most popular effect size measure is defined as $$ \delta = \frac{\mu_1 - \mu_2}{\sigma} $$ where $\mu_1$ and $\mu_2$ are the population means of the two population and $\sigma$ is the population standard deviation which is assumed to be the same for the two populations.$$ g = d\times \frac{\Gamma(m/2)}{\sqrt{(m/2)} \Gamma[(m-1)/2]} $$$m = n_1 + n_2 - 2$$g$$$ var(g) = \frac{m(1+\tilde{n} \delta^2)}…

cohen_s_d

johnny (johnny@undisclosed.example.com) — 2025-04-27T18:02:08+00:00

Cohen's d for independent two-sample design Calculator ---------- For studying the standardized group mean difference in an independent two-sample design, the most popular effect size measure is defined as $$ \delta = \frac{\mu_1 - \mu_2}{\sigma} $$ where $\mu_1$ and $\mu_2$ are the population means of the two groups and $\sigma$$$ d = \frac{\bar{y}_1 - \bar{y}_2}{\sqrt{\frac{(n_{1}-1)s_{1}^{2}+(n_{2}-1)s_{2}^{2}}{n_{1}+n_{2}-2}}} $$$n_1$$n_2$$\bar{y}_1$$\bar{y}_1$$s_1^2$$s_2^2$$\lambda…

nonormal3.png - created

johnny (johnny@undisclosed.example.com) — 2025-04-05T01:22:28+00:00

nonormal2.png - created

johnny (johnny@undisclosed.example.com) — 2025-04-05T01:22:28+00:00

nonormal1.png - created

johnny (johnny@undisclosed.example.com) — 2025-04-05T01:22:28+00:00

test.csv - created

johnny (johnny@undisclosed.example.com) — 2024-01-07T02:35:25+00:00

m58fig.png - created

ziqian (ziqian@undisclosed.example.com) — 2023-04-12T18:57:46+00:00

simplemed.png - created

johnny (johnny@undisclosed.example.com) — 2022-09-26T12:00:41+00:00

avata.png - created

johnny (johnny@undisclosed.example.com) — 2022-01-06T02:34:58+00:00

modmed15.png - created

anqi (anqi@undisclosed.example.com) — 2021-12-20T14:22:31+00:00

modmed14.png - created

anqi (anqi@undisclosed.example.com) — 2021-12-20T13:45:13+00:00

modmed7.png - created

anqi (anqi@undisclosed.example.com) — 2021-12-13T06:19:14+00:00