1. AIDS and AZT
Read the article "Study Challenges AZT Role As the Chief Drug for H.I.V."
1. If drug A is better than drug B, and drug B is better than nothing, is drug A better than nothing? Why or why not?
   
2. Are you concerned about the dropout rate in this study? give your reasons.
   
3. What other issues or concerns do you have about this study?
   

2. Coin tosses


1. In a study on how people perceive probability, Kahneman and Tversky asked subjects ``which of the following two sequences is more likely: H T H T T H or H H H T T T ? " Most people will say the first sequence. Why do you think they say this?
   
2. If a fair coin is tossed three times there will be 0, 1, 2, or 3 heads. How likely is each of these four possibilities?
   

Journal Assignment

1. Read the articles in Chance database related to AIDS tests, and record your comments.
   
2. Perform experiments with coin tosses, do it in three ways: flip the> coin, balance the coin on edge and strike the table, spin the coin on edge. Do each trial 100 times, and record your probability.