June 17, 2019

# Why Do We Use Standard Deviation?

The standard deviation formula is very simple: it is the square root of the variance. It is the most commonly used measure of spread.

An important attribute of the standard deviation as a measure of spread is that if the mean and standard deviation of a normal distribution are known, it is possible to compute the percentile rank associated with any given score. In a normal distribution, about 68% of the scores are within one standard deviation of the mean and about 95% of the scores are within two standard deviations of the mean.

The standard deviation has proven to be an extremely useful measure of spread in part because it is mathematically tractable. Many formulas in inferential statistics use the standard deviation.

## Mike Shorr

Since 1994, Michael has been an on-the-floor market maker, Vice-President of Interest Rate Derivatives for Knight Financial Products and Director of Education and Options Instructor at Trading Advantage. He makes the oftentimes complex world of options and trading accessible to the novice and advanced trader alike. Michael has a Bachelor of Science degree in Statistics and Finance from the University of Illinois Champaign-Urbana. He presently is Director, Trader Education at ProsperTradingAcademy.

May 8, 2024

## What Is Delta In Options Trading?

Understanding the Delta of an option is crucial for both new and seasoned traders. It’s one of five specific calculations called “Greeks,” which help measure specific factors that could influence the price of an options contract. Delta is a metric that helps you gauge how much the value of an option contract is expected to […]

March 28, 2024

## Wait! There Is An Options Greek Called Rho?

Out of all the Greeks in options trading, Rho is capable of providing uniquely critical insights that others cannot offer. Rho measures an option contract’s susceptibility to changing interest rates. We’ll explain how Rho by defining its specific functions, how interest rates impact options trading, and cover some pertinent scenarios. What is Rho in Options […]

March 25, 2024

## You Have A Lot Of Options Out There

There are a number of different types of options expiration types.  In the vast majority of our signals, our options will be categorized as “American”-style options.  There are some, like VIX options, that are “European”-style options.  Here’s a quick explanation of both. The term “American style” in relation to options has nothing to do with […]

May 8, 2024

## What Is Delta In Options Trading?

Understanding the Delta of an option is crucial for both new and seasoned traders. It’s one of five specific calculations called “Greeks,” which help measure specific factors that could influence the price of an options contract. Delta is a metric that helps you gauge how much the value of an option contract is expected to […]

March 28, 2024

## Wait! There Is An Options Greek Called Rho?

Out of all the Greeks in options trading, Rho is capable of providing uniquely critical insights that others cannot offer. Rho measures an option contract’s susceptibility to changing interest rates. We’ll explain how Rho by defining its specific functions, how interest rates impact options trading, and cover some pertinent scenarios. What is Rho in Options […]