Crash Commercial airplanes have an excellent safety record. Nevertheless, there are crashes occasionally, with the loss of many lives. In the weeks following a crash, airlines often report a drop in the number of passengers, probably because people are afraid to risk flying. a) A travel agent suggests that since the law of averages makes it highly unlikely to have two plane crashes within a few weeks of each other, flying soon after a crash is the safest time. What do you think? b) If the airline industry proudly announces that it has set a new record for the longest period of safe flights, would you be reluctant to fly? Are the airlines due to have a crash?

Calculating Probability and Drawing Inference using Central Limit Theorem for mean: - Ex1. Determining whether the mean lifetime claimed by a light bulb company is true in reality (refer to lecture 19 for a thorough example) - Statistical significance is when an effect in a study is real, and not likely to be due to random variation alone - Scheme of statistical inference (similar to proof by contradiction): o Initial claim/presumption o Observe (conduct study) and model (a distribution assuming claim) o Calculate probability (likeliness of observation if claim were true) o