Slot machine A slot machine has three wheels that spin independently. Each has 10 equally likely symbols: 4 bars, 3 lemons, 2 cherries, and a bell. If you play, what is the probability that a) you get 3 lemons? b) you get no fruit symbols? c) you get 3 bells (the jackpot)? d) you get no bells? e) you get at least one bar (an automatic loser)?

Statistical Reasoning and Practice Week 1 8/31/16 Big Picture: - Data teaches us about the world - There is natural variation in data But if variation is random, we can reduce it by increasing sample size - We then model variation and measure probability and error - We want to use random sampling and assignments to be able to make inferences about the world Basic terms: - Population: the group of people/things of interest - Sample: the subset of the population from which you get data (since you cannot measure an entire population) - Parameter (population parameter): this value summarizes/measures a characteristic of the population - Statistic (sample statistic): this value summarizes/measures a characteristic of the sample data and estimates