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The members of a population are numbered 1-50.

(a). Use Table I in Appendix A to obtain an SRS of size 6 from the population. Start at the two-digit number in line number 10 and column numbers 10-11, read down the column, up the next, and so on.

(b). If you have access to a random-number generator, use it to solve part (a)

Explain two ways in which descriptive statistics and inferential statistics are interrelated.

Oklahoma State Officials. The five top Oklahoma state officials are displayed in Table 1.2 on page 11. Use that table to solve the following problems.

(a) List the possible samples of size 1 that can be obtained from the population of five officials.

(b) What is the difference between obtaining a simple random sample of size 1 and selecting one official at random?

(c) List the possible samples (without replacement) of size 5 that can be obtained from the population of five officials.

(d) What is the difference between obtaining a simple random sample of size 5 and taking a census of the five officials?

Oklahoma State Officials. The five top Oklahoma state officials are displayed in Table 1.2 on page 11. Use that table to solve the following problems.

(a). List the 10 possible samples (without replacement) of size 3 that can be obtained from the population of five officials.

(b). If a simple random sampling procedure is used to obtain a sample of three officials, what are the chances that it is the first sample on your list in part (a)? the second sample? the tenth sample?

Keno. In the game of keno, 20 balls are selected at random from 80 balls numbered 1-80.

(a) Use Table I in Appendix A to simulate one game of keno by obtaining 20 random numbers between 1 and 80. Start at the two-digit number in line number 5 and column numbers 31-32, read down the column, up the next, and so on.

(b) If you have access to a random-number generator, use it to solve part (a).

The International 500. Each year, Fortune Magazine publishes an article titled "The International 500" that provides a ranking by sales of the top 500 firms outside the United States. Suppose that you want to examine various characteristics of successful firms. Further suppose that, for your study, you decide to take a simple random sample of 10 firms from Fortune Magazine's list of "The International 500."

(a) Use Table I in Appendix A to obtain 10 random numbers that you can use to specify your sample. Start at the three-digit number in line number 14 and column numbers 10-12, read down the column, up the next, and so on.

(b) If you have access to a random-number generator, use it to solve part (a).

Element Hunters. In the article "Element Hunters" (National Geographic, Vol. 233, No. 5, pp. 112-120), R. Dunn reports about the search for new undiscovered elements. Since 1940, scientists have been synthesizing elements one by one. The first was neptunium (Np), element number 93. There are, as of this writing, a total of 26 new synthetic elements. The following table provides their element numbers and symbols.

(a) Suppose that you decide to take a simple random sample of eight of these new elements. Use Table I in Appendix A to obtain eight random numbers that you can use to specify your sample.

(b) If you have access to a random-number generator, use it to solve part (a).

Undercoverage. Oftentimes, an accurate and complete list of the population is unavailable. In such cases, one or more groups will be omitted from the sampling process because they are not listed as part of the population. This type of bias is called undercoverage.

(a) Explain why a sample survey of households will generally suffer from undercoverage.

(b) Provide another example where bias due to undercoverage is likely to occur.

Nonresponse. When responses are not obtained from some of the individuals in the sample because either those individuals cannot be reached or refuse to participate, we have nonresponse bias.

(a) Discuss some of the dangers of nonresponse.

(b) Many sample surveys that are reported in the media have rates as low as 10%. Explain the consequences of such low response rates in trying to generalize the results to the entire population.

Ideally, in cluster sampling, each cluster should the entire population.