1. Thinking Critically About Psychological Science

2. A Questionnaire Instructions: Below are a number of factual questions, each of which has two possible answers. We are interested in studying the perceived difficulty of these items. In each case, one answer has a blank beside it which may or may not be the correct answer. In the blank, assign a probability that it is in fact the right answer.

3. A Questionnaire Here is a sample question: Absinthe is a. a precious stone ____% b. a liqueur Your task on this would be to indicate what probability (from 1 to 100%) you believe that absinthe is indeed a liqueur. For example, if you are pretty sure that absinthe is a liqueur, you might mark, say, 85%. If you felt equally sure that absinthe is not a liqueur, you might put 15%. If you felt it 50--50 (you have no idea), you might put 50%. In summary, your task is simply to estimate what odds you would give that the answer next to the blank is the correct answer.

4. Let’s Make a Deal!

5. Let’s Make a Deal (Old Days!) Monty Hall

7. Monty Hall Problem Example of OVERCONFIDENCE Truth of the matter is… We tend to be more confident than correct! Another example: – WREATWATER – ETRYNENTRYRESAI – GRABEBARGE

8. Remember That Questionnaire? Now respond to these questions. Instructions: Below are a number of factual questions, each of which has two possible answers. We are interested in studying the perceived difficulty of these items. The correct answer has a blank beside it. Pretend you hadn't been told the right answer. What probability would you have assigned to the answer with the blank beside it?

9. Remember That Questionnaire? Absinthe is a. a precious stone ____% b. a liqueur

10. Remember That Questionnaire?

11. Hindsight Bias “I-knew-it-all-along” phenomenon The tendency to believe, after learning an outcome, that one would have foreseen it. Other examples: – 9/11 – Virginia Tech Massacre

12. Bottom Line Hindsight bias and overconfidence often lead us to overestimate our intuition. These errors show why we need rigorous psychological research.