Runs Test for Detecting Non-Randomness using Excel The goal of any continuous improvement program is having a process that exhibits a state of statistical control. So, having a way to detect when a process is going out of statistical control is an important feature of a monitoring system. A system that exhibits statistical control yields […]

# Statistical Engineering

## Runs Test for Detecting Non-Randomness using Excel in 10 Steps

## 12 Steps to Testing for Normality using Excel 2016#### Learn how to Test for Normality using the Anderson Darling Statistical Procedure

Testing for normality using Excel is a routine procedure for Quality Engineers. In this post, I’ll show you how to test for normality using the Anderson Darling procedure. Using this procedure we will learn how to compute the Anderson Darling test statistic and p-value for a normal distribution. We will also compute an Anderson Darling […]

## Estimating the d2 constant and the d3 constant using Minitab

In this video tutorial I show how you can estimate the d2 constant and d3 constant. Employing Minitab, we will generate k = 1 million subgroups where each subgroup has n=2 values. Using this simulated data, we will estimate the control chart constants; d2 and d3. For this case, the real value of the d2 […]

## When to use an Xbar R Chart versus Xbar S Chart ?

Xbar R Chart versus Xbar S Chart I recently got a question from a reader that wanted to know when to use an Xbar R chart versus Xbar S chart. In this post, I will answer that question. Well, the decision to use either of these Statistical Process Control Charts comes down to how the […]

## Xbar and R Chart Formula and Constants | The Definitive Guide

Have you ever had to prepare an Average and Range Chart? If so, you most likely used some type of software package to display your data and compute the necessary control limits for your Xbar and R chart. But, have you ever wondered how these control limits for an Xbar and R chart were computed? […]