Intuition might tell you that hashing one billion records with SHA-256 is fine, there’s just too many different possible outputs for it to go wrong. … Read More

Before you start gathering results, decide how many answers you’ll need to reach. A simple rule of thumb is this: use standard formula for estimating … Read More

It’s easy to enter both sets of numbers in the two columns and see if there is any connection at all. Perhaps it’s the amount … Read More

One number stands out from survey results. You see fifty-four percent approve. Maybe you’re confident now that you know. But here’s where it’s dangerous: what … Read More

Take a number. It is something you got out of a textbook problem or based off of a spreadsheet. Until you turn it into a … Read More

It is the scale. That’s where you begin. There is a number. Maybe it’s low. Maybe it’s high. So you check growth charts. Are your … Read More

This page contains a calculator that computes probabilities using standard normal curve. We use this as a reference curve because any bell-shaped distribution with mean … Read More

Most quality- and risk-related decisions is driven by the quiet engine of the normal distribution. Your commuting time follow a normal distribution. Your test scores … Read More

This page’s standard deviation of a population calculator is a measure of just how closely (or loosely) all members of a set of number cluster … Read More

Or maybe it’s a list of numbers… Your daily sales figure at your store, or your exam scores from your last class. Averages are great; … Read More