Do Now What does it mean to be biased?

Objectives 22.February.2011 Students will be able to… Define bias and fallacy List different types of bias and fallacies.

Agenda Do Now (5 min) Review Test (10 min) Bias and Fallacies (15 min) Confirmation Bias (10 min)

Test Need to make up: Amber Jones Ivan Mendez A lot of good scores. Score has been curved so that it is now out of 37 instead of 43.

Test An airline company advertises that 100% of their flights are on time after checking 5 randomly selected flights and finding that these 5 were on time. “38% of adults in the United States regularly visit a doctor.” This conclusion was reached by a college student after she had questioned 520 randomly selected members of her college. What is wrong with her survey? In an article on msnbc.com titled “Windows Phone 7 may be contender in 2011” contains the line, “Msnbc.com is a joint venture of Microsoft and NBC Universal.” Why does it need to contain this line? An internet survey that took place mid-December last year asked the question, “Which do you prefer?” with the options “A real tree” or “A fake tree.” Among the 7073 responses received, 4650 indicated a real tree, and 2423 indicated a fake tree. Therefore, the site conclude most people prefer real trees. List two problems with that conclusion (extra credit for any additional problems you can identify.)

Test Random… Random is very hard. If I were to pick “5 random students” you can be sure the results would not be random, because humans are not capable of making random numbers. More on this later

Bias and Fallacy Bias means to favor one perspective at the expense of other equally or more valid perspectives. A fallacy is incorrect logic or reasoning resulting in a misconception.

List of Fallacies and Biases Appeal to ridicule Appeal to ignorance Appeal to emotion Begging the question Cum hoc ergo propter hoc Post hoc ergo propter hoc Gambler’s fallacy Historian’s fallacy Presentism Moving the goalpost Straw Man Selection Bias Systemic Bias Detection Bias Confirmation Bias Outcome Bias Sampling Bias Hindsight Bias Projection Bias

Confirmation Bias