How normal is your data? I mean, does your sample seem to represent the population well? Does your data have a regular pattern? Is your data precise or vague? In statistics, we answer these questions using measures of central tendency and measures of dispersion. There are three big measures that help determine if your data […]

## Understanding Variance Analysis

In statistics, you often want to compare several groups to each other to see if there are differences. These comparisons often use variance analysis. Statistical comparisons can often involve numerous groups and variables, but luckily there are several test designed specifically for analyzing the variance between these groups. Variance Analysis Basics In its most basic […]

## What is Sampling Variability? And Why is it Important?

You can’t always get what you want, but if you try sometimes, you get what you need. In terms of statistics, we want to know everything that there is to know about a group (or population). But sometimes that is just not feasible. Instead, we deal with approximations of a smaller group (or sample) and […]

## Sampling and Sampling Distributions

Sampling and sample distributions are the foundation of all inferential statistics. To conduct inferential statistics, you have to compare a sample to some sort of distribution. Sampling The overall goal of statistics is to determine patterns represented in a sample that reflect patterns that may exist in the population. The sample is a group of […]

## Scatter Plots and Correlation

In statistics, you deal with a lot of data. The hard part is finding patterns that fit the data. To look for patterns, there are several statistical tools that help identify these patterns. But before you use any of these tools, you should look for basic patterns. You can identify basic patterns using a scatter […]

## How to Perform an Independent Sample t-Test

I am addicted to caffeine. I mean I drink coffee, sodas, and even want to wake up with a little bit of chocolate. Sadly, my hand starts to shake a little bit right after I drink something with caffeine. But I am always wondering which drinks make my hand shake a little bit: coffee or […]

## What is the Law of Probability?

I like to play gin rummy, so I am always thinking about the probability of getting specific cards. Probability is a fantastic thing for prediction but it can be a little messy to figure those predictions too. Fortunately, there are a few basic principles (or laws) that help figure those probabilities out. Let’s investigate some […]

## Introduction to Regression Analysis

I love Oreos – I mean LOVE them. About once a year, I will eat an entire pack in one sitting and feel both proud and ashamed. But I always wonder, do I eat them because I’m hungry or because they are conveniently located at hand level at the grocery store. Many stores actually study […]

## What is Random Walk Theory?

A random walk describes the movement of an object along some mathematical space, or the different values generated by a random variable. Random walks have applications in Finance, Economics, Chemistry, Physics, and more. In this article, we’ll introduce the idea of random walks and Random Walk Theory.

## Markov Chains

A Markov chain is a memoryless stochastic process, meaning that future states of the system depend only upon the current state. In this article, we introduce the concept of a Markov chain and examine a few real-world applications.