# Resources

Explore our helpful guides for understanding key concepts in data analysis

### Statistics Guide

A concise guide to doing statistical analyses with GraphPad Prism 8.

### Curve Fitting Guide

A guide to fitting curves (and lines) with GraphPad Prism 8.

### Prism 8 User Guide

Guided examples of common analyses to get you started.

### QuickCalcs

Use our online calculators to run quick statistical tests.

## What's New?

## Explore Our Guides

## Statistics Guide Popular Topics

## Curve Fitting Guide Popular Topics

- Principles of Simple Linear Regression
- How to Fit a Model with Nonlinear Regression in Prism
- Example: Interpolating Data from a Sigmoidal Standard Curve
- Multiple Regression with Prism
- Equation: Receptor Binding – One Site – Specific
- Equation: log(Agonist) vs. Response -- Variable Slope
- Understanding r
^{2}in Linear Regression - Browse Curve Fitting Guide

## QuickCalcs

Run statistical analyses quickly and directly in your browser

## Categorical data

Fisher's, Chi square, McNemar's, Sign test, CI of proportion, NNT (number needed to treat), kappa.

## Continuous data

Descriptive statistics, detect outlier, t test, CI of mean / difference / ratio / SD, multiple comparisons tests, linear regression.

## Statistical distributions and interpreting P values

Calculate P from t, z, r, F or chi-square, or vice-versa. View Binomial, Poisson or Gaussian distribution. Correct a P value for multiple comparisons and Bayes.

## Random numbers

Assign subjects to groups, simulate data.

## Chemical and radiochemical data

Create and convert molar solutions, convert moles & grams, radioactivity calculations.

## Explore the Knowledgebase

### Popular Articles

- What is the meaning of * or ** or *** in reports of statistical significance from Prism or InStat?
- What is the difference between ordinal, interval and ratio variables? Why should I care?
- What is the difference between correlation and linear regression?
- 50% of what? How exactly are IC50 and EC50 defined?
- Probability vs. Odds
- The distinction between confidence intervals, prediction intervals and tolerance intervals
- Choosing a Statistical Test
- What does it mean when some results have e in the number?
- Why use n-1 when calculating a standard deviation?

- What you can conclude when two error bars overlap (or don’t)
- How to report P values in journals
- Is it better to plot graphs with SD or SEM error bars? (Answer: Neither)
- How to create a 100% stacked column graph
- How do I transpose columns and rows of a Prism data table?
- Graph tip – How to put a gap (or gaps) in an axis
- Graph tip – How can I plot an odds ratio plot, also known as a Forest plot, or a meta-analysis plot?
- Understanding the ANOVA table (SS, df, MS, F) in two-way ANOVA
- How to compare two means when the groups have different standard deviations
- How can I determine an EC90 (or any EC value other than EC50)?