Exercises

1. Imagine that you want to estimate the proportion of the population of American voters who consider themselves Democrats. Assuming that you can select randomly from among the voters, and each person you select tells us the truth (two conditions that are hard to satisfy in actual practice), and assuming that both Democrats and non-Democrats are not extremely rare:
   1. How many voters do you need to ask in order to achieve an estimate that you are 95% confident is within 10% of the true proportion?
   2. How many voters do you need to ask in order to achieve an estimate that you are 99% confident is within 2% of the true proportion?