GraphPad InStat

A less cumbersome alternative to typical heavy-duty statistical programs

Most statistics programs are designed by statisticians, for statisticians. These programs are feature-packed and powerful, but can overwhelm scientists with thick manuals, obscure statistical jargon and high prices. GraphPad InStat is different. InStat is designed by a scientist for scientists. With InStat, even a statistical novice can analyze data in just a few minutes.

Why Choose InStat?

Five reasons why you should choose InStat:

InStat guides you step by step

InStat conquers the learning curve by escorting you through statistical analyses. You'll master the program in just a few minutes – really.

Clear analysis choices with explanations

You don't have to know the name of the test you need. InStat helps you pick an appropriate test by asking questions about your data. If you are unsure, consult the extensive help screens, which explain the statistical reasoning in plain language.

Easy to understand results

InStat does not assume that you are a statistics whiz. It presents results in simple paragraphs, with a minimum of statistical jargon. InStat's help screens review the use of each test and explain every portion of the results.

Unique analysis checklists

With other statistics software, it is too easy to get the right answer to the wrong question. That's why InStat provides a unique analysis checklist. Double-check that your data have not violated any assumptions of the test, and that you have picked a test that matches your experimental design and really answers the question you had in mind.

A bargain

Most other statistics programs cost several hundred dollars, but we've made InStat affordable for everyone.

Features

InStat system requirements

Windows version – 486 or better, Windows 3.1 or higher, 4Mb RAM, 3Mb free hard disk space.

Macintosh version – OSX 10.3 (Panther) or higher and 4Mb free hard disk space. InStat 3 Mac is a native OS X (carbon) application. InStat Mac will not run under OSX 10.7 (Lion) or higher.

Cross platform compatible

InStat 3.0 is available both for Macintosh and Windows. The two versions are very similar. You can open files created on one platform on the other platform with no special conversion. The program has almost identical interfaces on the two platforms, so you can switch back and forth with virtually no learning curve.

Column statistics

Mean, median, 95% CI, SD, SEM. Also tests whether the distribution conforms to a Gaussian distribution using the Kolmogorov-Smirnov test.

Group comparisons

Paired and unpaired t tests; Mann-Whitney and Wilcoxon nonparametric tests.

Ordinary and repeated measures ANOVA followed by Bonferroni, Tukey, Student-Neuman-Keuls or Dunnett post tests.

Kruskal-Wallis or Friedman nonparametric tests followed by Dunn post test.

Contingency tables

Chi-square test with or without Yates’ continuity correction.

Chi-square test for linear trend.

Fisher’s exact test.

Calculate 95% confidence intervals for the relative risk, odds ratio or difference between two proportions.

Calculate the sensitivity, specificity, positive predictive value, negative predictive value and likelihood ratio with 95% confidence intervals.

Linear regression and correlation

Calculate slope and intercept with 95% confidence intervals.

Force the regression line through a specified point.

Interpolate from a standard curve.

Calculate correlation coefficient (Spearman or Pearson) and its confidence interval.

Test for departure from linearity with a runs test or the F test for linearity.

Multiple regression and correlation

Calculate a correlation matrix.

Multiple regression using selected X variables.

For each X variable, compute its best-fit coefficient with standard error and 95% confidence interval, and a P value testing whether the variable contributes significantly to the model.

Compute the Variance Inflation Factor (VIF) to test for multicollinearity.

Program features

Up to 10,000 rows and 52 columns of data.

Mathematically transform selected data (i.e., log, reciprocal, logit, etc.).

Transpose rows and columns.

Copy results or data to the clipboard, or export as a text file.

Print graphs on any printer or export as Windows Metafile (.WMF) or PICT (Mac) files.

Annotate your data and analyses using a built-in notes editor.

InStat files contain analysis choices as well as data so you can quickly rerun the same test with new data.

Combine 2 columns (add, subtract, multiply, divide) to create a new column.

Import comma or tab delimited files.

Import indexed (stacked) data, entire tables or selected rows and columns, filter selected data.

Export the data table as a text table, or as indexed (stacked) file.

Exclude selected values. They appear on the data table, but are treated as missing values by the analyses.

Graphing capabilities

InStat makes notebook quality graphs (not editable). For publication quality graphs, use GraphPad Prism.

GraphPad Prism's official website: http://www.graphpad-prism.cn/