1			The sampling method which involves selecting a random sample of m groups and then selecting a random sample of n elements from each of the selected groups is called sampling.
			A)	stratified random
			B)	simple random
			C)	single-stage cluster
			D)	two-stage cluster
			E)	systematic sampling
2			The number of strata should preferably be less than or equal to what value?
			A)	6
			B)	10
			C)	30
			D)	2
			E)	none of the above
3			The weight of stratum i is equal to the proportion of:
			A)	items sampled in stratum i compared to the number of items in the entire stratum.
			B)	the size of stratum i in the whole population.
			C)	those responding in stratum i compared to the number of people in the stratum.
			D)	the number of strata compared to the entire population.
			E)	none of the above
4			Census records indicate that in a geographic region, heads of households are distributed (proportionally) as follows: <a onClick="window.open('/olcweb/cgi/pluginpop.cgi?it=jpg::::/sites/dl/free/0073373605/582623/Ch16_q4.JPG','popWin', 'width=NaN,height=NaN,resizable,scrollbars');" href="#"><img valign="absmiddle" height="16" width="16" border="0" src="/olcweb/styles/shared/linkicons/image.gif"> (10.0K)</a> If a researcher randomly samples 100 observations in each population category then his __________ sample will be __________.
			A)	Stratified; proportional
			B)	Stratified; non-proportional
			C)	Systematic; non-proportional
			D)	Cluster; proportional
			E)	None of the above
5			A university has 5,000 students, belonging to the following classes: 1,500 are freshmen, 1,200 are sophomores, 1,400 are juniors, and 900 are seniors. The university administration wants to get an estimate of all the students views on a proposal to help alleviate the parking problem on campus. Suppose that a sample of 100 students is chosen. What is the required sample size for the freshman stratum under proportional allocation?
			A)	3
			B)	33.3
			C)	30
			D)	50
			E)	none of the above
6			When the number of observations drawn from a stratum is small relative to the overall size of the stratum then the ___________ will be small also.
			A)	Error ratio
			B)	Stratified proportion
			C)	Sampling fraction
			D)	Fractional error
			E)	None of the above
7			In stratified random sampling with strata weights 0.35, 0.55 and 0.10, and standard deviations 16, 23 and 19, and sample sizes 70, 110 and 20, the variance of the sample mean estimator is?
			A)	2.72
			B)	2.27
			C)	1.65
			D)	1.56
			E)	None of the above

Use the following information to answer questions 8-10:

A population consists of three strata – A, B and C. Samples drawn from each stratum resulted in the following (assume that the sampling fraction is very small):

<a onClick="window.open('/olcweb/cgi/pluginpop.cgi?it=jpg::::/sites/dl/free/0073373605/582623/Ch16_q8.JPG','popWin', 'width=NaN,height=NaN,resizable,scrollbars');" href="#"><img valign="absmiddle" height="16" width="16" border="0" src="/olcweb/styles/shared/linkicons/image.gif"> (5.0K)</a>

8			In this instance, an unbiased estimate for the population mean would be___________
			A)	30.37
			B)	30.73
			C)	33.07
			D)	37.03
			E)	37.33
9			In this instance, an unbiased estimate for the variance of the sample mean estimator is ____________
			A)	0.466
			B)	0.468
			C)	0.644
			D)	44.34
			E)	43.43
10			In this instance a 95% confidence interval for the population mean is ____________
			A)	24.41 ≤ μ ≤ 50.25
			B)	24.11 ≤ μ ≤ 49.94
			C)	26.22 ≤ μ ≤ 47.84
			D)	36.11 ≤ μ ≤ 37.95
			E)	36.26 ≤ μ ≤ 37.90

Use the following to answer questions 11-12:

An internet retailer took 3,000 orders last week and management wants an estimate of the average number of items per order. An analyst has decided to use systematic sampling, with every 20^th "shopping cart" analyzed. The following observations are obtained via this method:

1, 2, 4, 1, 1, 3, 4, 2, 2, 1, 3, 3, 2, 1, 1, 4, 2, 1, 1, 3

11			Compute the systematic sampling estimator of the population mean.
			A)	3.2
			B)	1.2
			C)	2.1
			D)	2.3
			E)	1.1
12			Compute the estimated variance of the systematic sample mean estimator.
			A)	0.226
			B)	0.622
			C)	1.253
			D)	1.352
			E)	None of the above