This free online video program "shows how to improve the accuracy of a survey by using stratified random sampling and how to avoid sampling errors such as bias. While surveys are becoming increasingly important tools in shaping public policy, a 1936 Gallup poll provides a striking illustration of the perils of undercoverage."
Email Address:
Technical Requirements:
Windows media player, broadband connection, Java script enabled
Source Code Available:
Source Code Available
Intended User Role:
Learner, Teacher
Material Type:
Resource Type:
Statistical Topic:
Copyrights:
Yes
Cost:
Free for All
Audience:
Math Level: