Can a bias affect the strength of an inductive argument in a public opinion poll, such as a vague generality in the property in question?
Inductive arguments are arguments in which the arguer only intends to affirm the conclusion as probably, or likely. In contrast, using deductive arguments, the arguer intends to confirm the conclusion is true through the argument's premises. The staff writers of the Internet Encyclopedia of Philosophy give us the following simple example of an inductive argument:
- Every time I've walked by that dog, he hasn't tried to bite me. So, the next time I walk by that dog he won't try to bite me.
The following contrasting example of a deductive argument is also given:
- It's sunny in Singapore. If it's sunny in Singapore, he won't be carrying an umbrella. So, he won't be carrying an umbrella.
Inductive arguments must be used in analyzing public opinion poll samples because, since only a sample of the public can logically be polled as opposed to all of the public, not all of the premises of the argument can possibly be known; therefore, those who analyze and reach conclusions based on the poll sample must use inductive reasoning. One problem with analyzing polls through the requisite inductive reasoning is that certain fallacies can be used in inductive reasoning, which include hasty generalization, weak analogy, appeal to unqualified authority, false cause, slippery slope, and appeal to ignorance. One of the fallacies that can result from bias is the fallacy of hasty generalization. Bias is demonstrated in public polls when the sample is not fully representative. Hasty generalizations happen when the arguer draws a conclusion he/she thinks can be applied to a far more general group than is really true. Hence, when the poll sample is biased, the poll will inevitably lead to hasty generalizations. Found on the Cuesta Community College website, an instructor-posted informational article concerning the fallacies of a weak inductive argument gives us the following example of an inductive argument containing a hasty generalization due to bias:
This survey is conclusive proof that Americans are in favor of immediate military strikes against all sites identified as terrorist training camps. It polled a wide range of students at all three of our elite military academies, and 85 percent of them were in favor of such strikes.
Cuesta Community College also lists a famous example in which Literary Digest magazine predicted that Republican elect Alf Landon would win the Presidential election against Franklin Delano Roosevelt in 1936. The problem was that, according to Cuesta Community College, the magazine only polled vehicle owners and individuals listed in the phone directory, in other words, people who were still fairly well off during the Great Depression, so people who were more likely to vote Republican than Democrat. Hence, as we can see, yes, bias certainly can affect the inductive argument based on a public opinion poll, especially due to hasty generalization, which can be due to bias.