Stratification And Synthesis Essay

If the questions are not themselves biased, most bias can be eliminated by stratifying the sample.

Stratification is the process of sorting the sample into groups (“strata”) that have been identified in advance as highly relevant to the issue being studied. For instance, when the topic is abortion, both a person’s sex and religious affiliation will influence his or her position. If we cannot get a highly random sample, then we should stratify our sample for at least these two factors. So in addition to asking them whatever we want to know, we need to determine these additional facts. If we sample more than we really need, we can then sort the sample into the relevant subgroups, see if any are over-represented, and then randomly eliminate

samples

Confirming evidence is a special case of biased sample. This is the special case of using a method that gets the arguer or researcher a result favorable to his or her desired conclusion. The method can create this bias either intentionally or accidentally. Either way, the fallacy consists in choosing a method that generates a large sample of one very specific, highly unrepresentative group. There are two ways to generate confirming evidence. One is to use a method that initially selects a sample from one particular group. For example, if I want to know how many Americans think that it’s time for a woman to become the U.S.

President, then I would generate confirming evidence if I only called women. It would be even worse if I only called women whose telephone numbers were provided by N.O.W. (the National Organization for Women).

Similarly, if I’m interesting in supporting the idea that video games harm children, I might generate my sample of children by choosing children at a juvenile corrections facility.

The other method to generate confirming evidence is to ask a question that automatically favors one answer over other possible answers. If I want to “discover” strong support for private schools, I might ask people,