Six Sigma For Dummies, 2nd Edition

Chapter 16

Making Confident Decisions

In This Chapter

Distinguishing populations and samples

Surveying sampling distributions and the central limit theorem

Establishing confidence intervals for population means, variances, and proportions

Which truck is better, Ford or Chevy? Which spread is better for you, butter or margarine? From public opinion polls to medical treatment reports to climate studies, the media literally bombards you with “scientific” information on these types of issues. Unfortunately, you don’t always have sufficient evidence or the analytical skills you need to make the best choices. But you can make the best choices when it comes to your Six Sigma processes.

In this chapter, we share the tried-and-true methods to help you make the best decisions in your business and feel confident about them. After all, when you’re operating a business, finding the truth within data is paramount to consistent success. Is Process A better than Process B? Which marketing plan is more effective? Which facility is operating with higher quality? Has our new warehouse really reduced inventory costs? With this chapter, you can be the authoritative, in-the-know source.

Introducing Populations ...