# About Stat Trek

If this is your first visit to StatTrek.com, welcome. Our mission is to help you solve common statistics problems - quickly, easily, and cost-effectively.

## What We Do

We try to take the drudgery out of statistics by providing user-friendly instructional and analytical tools.

## About Our Tutorials

Stat Trek provides five free, online tutorials:

**Advanced Placement (AP) Statistics**. The AP Statistics tutorial is designed to help students master the Advanced Placement Statistics Examination.**Probability**. The Probability tutorial covers probability theory in aw-shucks language. Clear explanations and pages of solve probability problems.**Simple Linear Regression**. The Simple Linear Regression tutorial is a pain-free introduction to regression. It explains how to predict scores on one variable, based on scores on a second variable.**Survey Sampling**. The Survey Sampling tutorial describes three probability methods for selecting and analyzing sample data - simple random sampling, stratified sampling, and cluster sampling.**Matrix Algebra**. The Matrix Algebra tutorial is an easy-to-understand introduction to matrix algebra. It covers matrix nomenclature, matrix notation, and common matrix operations.

Topics are introduced in short, easy-to-understand lessons. Technical terms are linked to their definitions; so online help is just a mouse click away.

# Cross Site Scripting

- How your website can be attacked.
- How to protect your website.

## About Our Analytical Tools

We offer a wide range of analytical tools to support topics covered in the tutorials. These tools include:

**Statistical tables**. We provide online statistics tables for each of the following nine distributions: binomial, chi-square, f-distribution, hypergeometric, multinomial, negative-binomial, normal, poisson, and t-distribution.**Online calculators**. We have all kinds of online calculators: a Bayes rule calculator, a calculator that computes the number of combinations and permutations, a calculator that computes factorials, and a general probability calculator that computes probabilities of one event, based on probabilities of other events.**Random number generator**. The random number generator produces lists of up to 1000 random numbers, based on user specifications.**Sample Size Calculator**. The Sample Size Calculator creates powerful, cost-effective sampling plans tailored to your research needs.

Each analytical tool features clear instructions, provides answers to frequently-asked questions, and includes sample problems with solutions.

## About Our Pricing

All of Stat Trek's analytical tools and training services are free, accessible to anyone who visits the website. There are no licensing fees or log-in requirements.

## Who We Are

Stat Trek was founded by Harvey Berman. Harvey earned a bachelors degree in Industrial Engineering and a PhD in Psychology, both from the Georgia Institute of Technology.

Following graduation, Harvey spent nearly two decades applying math and statistics skills to real-world problems, mainly in the areas of market research and strategic planning.

In 2000, Harvey left the corporate world to develop Stat Trek, an educational website devoted to helping people teach themselves statistics. In his spare time, Harvey plays golf and bridge - both poorly.