Fred wants to travel from Blotchville to Blissville, and is deciding between 3 options (involving dierent routes or dierent forms of transportation). The jth option would take an average of j hours, with a standard deviation of j hours. Fred randomly chooses between the 3 options, with equal probabilities. Let T be how long it takes for him to get from Blotchville to Blissville. (a) Find E(T). Is it simply (1 + 2 + 3)/3, the average of the expectations? (b) Find Var(T). Is it simply (2 1 + 2 2 + 2 3)/3, the average of the variances.
Exam 1: Study Guide Lecture 2: Rafia Chaudhary Statistics is the art and science of learning from data Individuals (also known as subjects, instances, and observations) are the things we get our data from. Who/what do we get our data from o These are often people, animals, or other living things but don’t need to be Variable: any characteristic or piece of information about an individual o Is an answer to a question, like how tall are you What’s your name etc. Ex: you are working for a drug company and you are developing a new drug to treat the common cold o Individuals: humans o Variables: measure of patient’s symptoms, time it takes f
