notes 10 - Designing Experiments Submitted by gfj100 on...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Designing Experiments Submitted by gfj100 on Tue, 11/10/2009 - 16:28 Example Suppose some group claims that drinking caffeinated coffee causes hyperactivity college students, ages 18 to 22. How would this group produce data to determine the validity of this statement? 1. Select some subset of college students of ages 18 to 22 and find their intake of caffeinated coffee. This would not be an experiment but rather an observational study : a part of the population is sampled and examined in order to gain information about the population. This is not an experiment because no treatment was imposed. Unfortunately, lurking variables can easily lead to unreliable results (e.g. other dietary intake, stress, family history). 2. Give caffeinated coffee to a randomly sampled group of college students over a period of time and observe their behavior. This would be an experiment because a treatment is imposed: the caffeinated coffee. This design would be an improvement over the observational study in that we can better pin down the effects of the explanatory variable,
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/31/2011 for the course STAT 200 taught by Professor Andyregards during the Spring '11 term at World College.

Ask a homework question - tutors are online