Question

1. Is it true that the sample mean is always equal to the population mean that we picked the sample from? Explain.

2. Is it true that the confidence interval is narrower for 95% confidence than for 90% confidence? Explain

3. Is it true that the Sample means are less variable than individual observations as n→∞ ? Explain

4. A newspaper article reports that the average income of Canadian adults is 45000 with a 90% confidence interval of 28000 to 62000. What is the interpretation of this confidence interval?

5. In a certain desert region, the number of people who become seriously ill each year from eating a certain poisonous plant is a random variable having a Poisson distribution with an average rate of 5.2 persons per year. Find the probability that at least 7 but fewer than 10 such illnesses will be observed in 2 years. Show your work

Answer 1