Warm Up A survey of 200 randomly selected California lottery ticket buyers asked them their age. The ages of the lottery players are listed below. Also listed below is the percentage of all Californians in the same age groups. 18-34 35-64 65 and over Lottery Players 36 130 34 Population 35% 51% 14% Is it reasonable to conclude that one or more of these age groups contains a disproportionate number of lottery players? 1) State appropriate hypotheses. 2) Create a table of observed and expected counts. 3) Calculate c2, df, and the p-value and make a conclusion.
Practice The 2010 research paper entitled “Is It Really About Me? Message Content in Social Awareness Streams” studied a random sample of 350 tweets. The tweets were classified into one of the following categories. Information Opinions/ Random Me (What I’m Sharing Complaints Thoughts Doing Now) Other 51 61 64 101 73 Carry out a significance test to determine if there is convincing evidence that the proportions of all tweets falling into each of the five categories are not the same. Use the 4 step process with a = 0.01.
Practice A biologist is tracking 2 genetic tendencies in beets: color and leaf shape. According to Mendel’s laws, the probability of inheriting both dominant traits is 9/16, one dominant and one recessive is 3/16 and both recessive is 1/16. Assume red color and smooth edge leafs are dominant. A random sample of 100 beet seedlings yields the following data. Red&Smooth Red&Cut Yellow&Smooth Yellow&Cut 53 22 18 7 1) Is this data consistent with Mendel’s laws? Conduct a significance test to explain why or why not. 2) Experts Only: Explain how we found the proportions used in Mendel’s Laws
Random Numbers on a Graphing Calculator We will use a Chi Square Test to determine if the ”random” numbers generated by your calculator are actually random. There are many ways to check if a set of numbers is truly “random.” We will use a simple test today – Is there evidence the number of times each number is generated is not the same for all numbers in your range? Follow the instructions on the worksheet. You will turn this in at the end of class. Remember, everyone’s calculator generates unique random numbers so everyone’s results will be different.