# Library

**Newsletter Archive** - full copies of past Division newsletters

**Statistics Body of Knowledge** - our library content below focuses on the topics in this listing.

**1**

### A Case Study in Sample Size

Statisticians are often asked questions related to sample size. However, they are often not well prepared to answer them. There are simple approximate sample-size formulas for such as two-sample t tests, and those can be pressed into service. But most studies are more complicated than that. In fact, often several effects come into play, and thus there are several aspects of the power/sample-size question. This article presents an example of a sample-size problem in a semiconductor experiment having a somewhat complex design. It is hoped that it helps to give some practical guidance in this confusing area.

- Filetype: pdf
- Publish date: 2014-03
- Keywords:Sample Size, Semiconductor experiments, Split-lot designs

### Is Deming's Red Bead Experiment Misleading?

Mini-Paper from the Jan 2013 Newsletter

This is the Mini-Paper in the January 2013 Newsletter...

- Filetype: pdf
- Publish date: 2013-01
- Keywords:Red beads, Rating Employees, Common cause, Sample Size, Power

### Sample Sizes and Marketing Campaigns

This paper compares two commonly used methods for determining sample sizes in marketing campaigns and provides guidelines for selecting the best method to satisfy business objectives...

- Filetype: pdf
- Publish date: 2008-01
- Keywords:Sample Size, Type 1 error, Type 2 error, Confidence interval, Hypothesis testing, Sample cost

### Application of Control Charting to Weibull Data

Mini Paper Taken from the Winter 1992 Newsletter

This paper presents an example of one possible use of Weibull statistics for quality control with lot type data...

- Filetype: pdf
- Publish date: 1992-01
- Keywords:Weibull distribution, Statistical process control, Maximum likelihood estimation, Normal distribution, Joint density function, Control charts, Sample Size, Normal plots, Wilk-Shapiro test, Moving range chat, Hotelling's T2 distribution, Correlation