Deck 7: Sampling and Sampling Distributions

Question 1

Nonsampling error occurs when, due to chance, the sample is not representative of the population.

Answer 1

False

Question 2

If every unit of the population has the same probability of being selected for the sample, then the researcher is conducting random sampling.

Answer 2

True

Question 3

Sampling errors cannot by determined objectively for nonrandom sampling techniques.

Answer 3

True

Question 4

A major limitation of nonrandom samples is that they are not appropriate for most statistical methods.

Question 5

Increasing the sample size causes the numerical value of the standard error of the mean to increase.

Question 6

Systematic sampling is a type of nonrandom sampling technique.

Question 7

In some situations sampling may be the only option because the population is inaccessible.

Question 8

The directory or map from which a sample is taken is called the frame.

Question 9

Cluster (or area)sampling is a type of random sampling technique.

Question 10

A nonrandom sampling technique which is similar to stratified random sampling is called quota sampling.

Question 11

The two major categories of sampling methods are proportionate and disproportionate sampling.

Question 12

With cluster sampling, there is homogeneity within a subgroup or stratum.

Question 13

If a researcher wants to study all students in their university and includes only those students in the researcher's class, then the researcher is conducting convenience sampling.

Question 14

Saving time and money are reasons to take a sample rather than do a census.

Question 15

A sampling distribution is the distribution of a sample statistic such as the sample mean or sample proportion.

Question 16

In a random sampling technique every unit of the population has a randomly varying chance or probability of being included in the sample.

Question 17

If a researcher selects every k^th item from a population of N items, then the researcher is likely conducting a stratified random sampling.

Question 18

The standard deviation of the sample means is commonly called the standard error of the mean.

Question 19

The central limit theorem states that if the sample size, n, is large enough (n ≥30), the distribution of the sample means is uniformly distributed regardless of the shape of the population.

Question 20

A population list, map, directory, or other source used to represent the population from which a sample is taken is called the census.

Question 21

Kristen Ashford purchased the subscribers list for Wind Surfing magazine.She plans to survey a sample of the subscribers before using the list in her mail order business.She randomly selects the fourth name as a starting point and then selects every 50th subsequent name (54, 104, 154, etc.).Her sample is a ___.

A)simple random sample
B)stratified sample
C)systematic sample
D)convenience sample
E)cluster sample

Question 22

Suppose 90% of students in some specific college have a computer at home and a sample of 40 students is taken.The probability that more than 30 of those in the sample have a computer at home can be approximated using the normal approximation.

Question 23

The mean of the sample means is the same as the mean of the population

Question 24

If every 15^th item is systematically sampled to produce a same size of 90 items, the population has 1,350 items.

Question 25

The sampling distribution of is close to normal provided that n≥30.

Question 26

Financial analyst Larry Potts needs a sample of 100 securities listed on the Toronto Stock Exchange.The current issue of the Report on Business Magazine, has an alphabetical list of the 2,531 securities that are listed in the "Toronto Exchange Composite Transactions," an alphabetical listing of all securities traded on the previous business day.Larry randomly selects the 7th security as a starting point, and selects every 25th security thereafter (7, 32, 57, etc.).His sample is a ___.

A)quota sample
B)simple random sample
C)stratified sample
D)systematic sample
E)cluster sample

Question 27

The sampling distribution of the sample means is less variable than the population distribution.

Question 28

Financial analyst Larry Potts needs a sample of 100 securities listed on either the Toronto Stock Exchange (TSX)or the New York Stock Exchange (NYSE).According to the Report on Business Magazine's "Stock Market Data Bank," 2,531 TSX securities and 746 NYSE securities were traded on the previous business day.Larry directs his staff to randomly select 77 TSX and 23 NYSE securities.His sample is a ___.

A)disproportionate systematic sample
B)disproportionate stratified sample
C)proportionate stratified sample
D)proportionate systematic sample
E)proportionate cluster sampling

Question 29

On Saturdays, cars arrive at David Zebda's Scrub and Shine Car Wash at the rate of 80 cars per hour during the ten-hour shift.David wants a sample of 40 Saturday customers to answer the long version of his quality service questionnaire.He randomly selects 9 as a starting point and instructs the crew to select the 9th customer and every 20^th customer thereafter (9, 29, 49, etc.).His sample is a ___.

A)convenience sample
B)simple random sample
C)unsystematic sample
D)stratified sample
E)systematic sample

Question 30

Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers.Accordingly, he plans a sample of waiting times for walk-in customers.Albert instructs his staff to record the waiting times for the first 45 walk-in customers arriving after the noon hour.Albert's sample is a ___.

A)simple random sample
B)systematic sample
C)convenience sample
D)stratified sample
E)cluster sample

Question 31

Financial analyst Larry Potts needs a sample of 100 securities listed on the Toronto Stock Exchange.The current issue of the Report on Business Magazine, has an alphabetical list of the 2,531 securities that are listed in the "Toronto Exchange Composite Transactions," an alphabetical listing of all securities traded on the previous business day.Larry uses a table of random numbers to select 100 numbers between 1 and 2,531.His sample is a ___.

A)quota sample
B)simple random sample
C)systematic sample
D)stratified sample
E)cluster sample

Question 32

Kristen Ashford purchased the subscribers list for Wind Surfing magazine.She plans to survey a sample of the subscribers before using the list in her mail order business.The names are numbered consecutively from 1 to 5,000.Kristen chooses her sample by selecting four-digit numbers (1 to 5,000)from a random number table.Her sample is a ___.

A)simple random sample
B)stratified sample
C)systematic sample
D)convenience sample
E)cluster sample

Question 33

On Saturdays, cars arrive at David Zebda's Scrub and Shine Car Wash at the rate of 80 cars per hour during the ten-hour shift.David wants a sample of 40 Saturday customers to answer the long version of his quality service questionnaire.He instructs the Saturday crew to select the first 40 customers.His sample is a ___.

A)convenience sample
B)simple random sample
C)systematic sample
D)stratified sample
E)cluster sample

Question 34

The sampling distribution of has a mean equal to the square root of the population
proportion p.

Question 35

The sampling distribution of the sample means is close to the normal distribution only if the distribution of the population is close to normal.

Question 36

If the population is normally distributed, the sample means of size n=5 are normally
distributed.

Question 37

Pinky Bauer, Chief Financial Officer of Harrison Haulers, Inc., suspects irregularities in the payroll system.She knows that 2,500 payroll vouchers have been issued since January 1, 2000, and her staff doesn't have time to inspect each voucher.So, she randomly selects 53 as a starting point and orders her staff to inspect the 53rd voucher and each voucher at an increment of 100 (53, 153, 253, etc.).Her sample is a ___.

A)stratified sample
B)simple random sample
C)convenience sample
D)cluster sample
E)systematic sample

Question 38

Kristen Ashford purchased the subscribers list for Wind Surfing magazine.She plans to survey a sample of the subscribers before using the list in her mail order business.She chooses the first 100 of the 5,000 names.Her sample is a ___.

A)simple random sample
B)stratified sample
C)systematic sample
D)convenience sample
E)cluster sample

Question 39

When determining the value of k the correct calculation is n/N.

Question 40

Pinky Bauer, Chief Financial Officer of Harrison Haulers, Inc., suspects irregularities in the payroll system.She knows that 2,500 payroll vouchers have been issued since January 1, 2000, and her staff doesn't have time to inspect each voucher.So, she orders her staff to inspect the last 200 vouchers.Her sample is a ___.

A)stratified sample
B)simple random sample
C)convenience sample
D)systematic sample
E)cluster sample

Question 41

According to the central limit theorem, for samples of size 169 drawn from a population with µ = 1,014 and σ = 65, the standard deviation of the sample means would equal ___.

A)1,014
B)65
C)15
D)6
E)5

Question 42

Alice Zhong is the VP of Operations at Pearl Financial Services.She wants to measure customer satisfaction after a new website and other changes were introduced a few months ago.For this purpose, she instructs her staff to prepare a questionnaire and send it to any IP address that accesses the company's website from 8 a.m.to 9 a.m.during each day of the next four weeks.This is an example of ______.

A)simple random sample
B)systematic sample
C)convenience sample
D)stratified sample
E)cluster sample

Question 43

According to the central limit theorem, if a sample of size 100 is drawn from a population with a mean of 80, the mean of all sample means would equal ___.

A)0.80
B)8
C)80
D)100
E)120

Question 44

Alice Zhong is the VP of Operations at Pearl Financial Services.She wants to measure customer satisfaction after a new website and other changes were introduced a few months ago.28% of clients are from the healthcare industry, 35% are manufacturing companies, 27% are financial firms, and 7% are construction companies.For this purpose, she gets random five-digits numbers from the website random.org (which offers true random numbers on the Internet).Then she uses these numbers to select 140 random clients from the healthcare sector, 175 from the manufacturing sector, 135 from the manufacturing sector, and 35 from the construction sector.This is an example of ______.

A)disproportionate systematic sample
B)disproportionate stratified sample
C)proportionate stratified sample
D)proportionate systematic sample
E)proportionate cluster sampling

Question 45

According to the central limit theorem, for samples of size 169 drawn from a population with µ = 1,014 and σ = 65, the mean of the sample means would equal ___.

A)1,014
B)65
C)5
D)6
E)3

Question 46

A carload of various palletized aluminum castings has arrived at Mansfield Motor Manufacturers.The car contains 1,000 pallets of 100 castings each.Mario Munoz, Manager of Quality Assurance, directs the receiving crew to deliver the 127th and 869th pallets to his crew for 100% inspection.Mario randomly selected 127 and 869 from a table of random numbers.Mario's sample of 200 castings is a ___.

A)simple random sample
B)systematic sample
C)stratified sample
D)cluster sample
E)convenience sample

Question 47

According to the central limit theorem, if a sample of size 81 is drawn from a population with a standard deviation of 72, the standard deviation of the distribution of the sample means would equal ___.

A)8
B)9
C)7.2
D)0.875
E)128.00

Question 48

Catherine Chao, Director of Marketing Research, needs a sample of households to participate in the testing of a new toothpaste package.She chooses thirty-six of her closest friends.Catherine's sample is a ___.

A)cluster sample
B)convenience sample
C)quota sample
D)systematic sample
E)random sample

Question 49

Alice Zhong is the VP of Operations at Pearl Financial Services.She wants to measure customer satisfaction after a new website and other changes were introduced a few months ago.For this purpose, she uses random five-digits numbers from the website random.org (which offers true random numbers on the Internet).This is an example of ______.

A)simple random sample
B)systematic sample
C)convenience sample
D)stratified sample
E)cluster sample

Question 50

Catherine Chao, Director of Marketing Research, needs a sample of households to participate in the testing of a new toothpaste package.She directs the seven members of her staff to find five households each.Catherine's sample is a ___.

A)cluster sample
B)proportionate stratified sample
C)quota sample
D)disproportionate stratified sample
E)simple random sample

Question 51

Alice Zhong is the VP of Operations at Pearl Financial Services.She wants to measure customer satisfaction after a new website and other changes were introduced a few months ago.For this purpose, she instructs her staff to prepare a questionnaire and send it to the first 200 clients in their alphabetical list of active clients.This is an example of ______.

A)simple random sample
B)systematic sample
C)convenience sample
D)stratified sample
E)cluster sample

Question 52

According to the central limit theorem, if a sample of size 100 is drawn from a population with a standard deviation of 80, the standard deviation of sample means would equal ___.

A)0.80
B)8
C)80
D)800
E)0.080

Question 53

Increasing the sample size causes the sampling distribution of to ___.

A)shift to the right
B)shift to the left
C)have more dispersion
D)have less dispersion
E)stay unchanged

Question 54

A carload of steel rods has arrived at Cybermatic Construction Company.The car contains 1,000 bundles of 50 rods of various sizes.Claude Ong, Manager of Quality Assurance, directs the receiving crew to deliver the 63rd and 458th bundles to his crew for 100% inspection.Claude randomly selected 63 and 458 from a table of random numbers.Claude's sample of 100 rods is a ___.

A)cluster sample
B)simple random sample
C)quota sample
D)systematic sample
E)stratified sample

Question 55

According to the central limit theorem, for samples of size 64 drawn from a population with µ = 800 and σ = 56, the mean of the sample means would equal ___.

A)7
B)8
C)100
D)800
E)80

Question 56

According to the central limit theorem, for samples of size 64 drawn from a population with µ = 800 and σ = 56, the standard deviation of the sample means would equal ___.

A)7
B)8
C)100
D)800
E)80

Question 57

Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers.Accordingly, he plans a sample of waiting times for walk-in customers.Albert randomly selects 4 as a starting point and instructs his staff to record the waiting times for the 4th walk-in customer and every 10th customer thereafter (4, 14, 24, etc.).Albert's sample is a ___.

A)simple random sample
B)cluster sample
C)convenience sample
D)stratified sample
E)systematic sample

Question 58

According to the central limit theorem, if a sample of size 64 is drawn from a population with a mean of 56, the mean of all sample means would equal ___.

A)7.00
B)56.00
C)64.00
D)0.875
E)128.00

Question 59

Abel Alonzo, Director of Human Resources, is exploring employee absenteeism at the Harrison Haulers Plant.Abel knows that absenteeism varies significantly between departments.For example, workers in the wood shop are absent more than those in the tuning department and the size of the departments ranges from 40 to 120 workers.He orders a random sample of 10% of the workers from each of the six departments.Abel's sample is a ___.

A)proportionate systematic sample
B)proportionate stratified sample
C)disproportionate systematic sample
D)disproportionate stratified sample
E)proportionate cluster sample

Question 60

Abel Alonzo, Director of Human Resources, is exploring employee absenteeism at the Harrison Haulers Plant.Abel knows that absenteeism varies significantly between departments.For example, workers in the wood shop are absent more than those in the tuning department and the size of the departments ranges from 40 to 120 workers.He orders a random sample of 10 workers from each of the six departments.Abel's sample is a ___.

A)proportionate systematic sample
B)proportionate stratified sample
C)disproportionate systematic sample
D)disproportionate stratified sample
E)proportionate cluster sample

Question 61

Suppose a population has a mean of 400 and a standard deviation of 24.If a random sample of size 144 is drawn from the population, the probability of drawing a sample with a mean less than 402 is ___.

A)0.3413
B)0.6826
C)0.8413
D)0.1587
E)0.9875

Question 62

Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers.Accordingly, he plans a sample of waiting times for walk-in customers.If the population of waiting times has a mean of 15 minutes and a standard deviation of 4 minutes, the probability that Albert's sample of 64 will have a mean less than 15 minutes is ___.

A)0.5000
B)0.0228
C)0.9072
D)0.9544
E)1.0000

Question 63

Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers.Accordingly, he plans a sample of waiting times for walk-in customers.If the population of waiting times has a mean of 15 minutes and a standard deviation of 4 minutes, the probability that Albert's sample of 64 will have a mean less than 16 minutes is ___.

A)0.4772
B)0.0228
C)0.9072
D)0.9544
E)0.9772

Question 64

Suppose a population has a mean of 90 and a standard deviation of 28.If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a mean between 85 and 95 is ___.

A)0.1056
B)0.3944
C)0.7888
D)0.2112
E)0.5000

Question 65

Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers.Accordingly, he plans a sample of waiting times for walk-in customers.If the population of waiting times has a mean of 15 minutes and a standard deviation of 4 minutes, the probability that Albert's sample of 64 will have a mean between 16.5 and 18.5 minutes is ___.

A)0.1865
B)0.2667
C)0.7333
D)0.5468
E)1.0000

Question 66

Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers.Accordingly, he plans a sample of waiting times for walk-in customers.If the population of waiting times has a mean of 15 minutes and a standard deviation of 4 minutes, the probability that Albert's sample of 64 will have a mean less than 14 minutes is ___.

A)0.4772
B)0.0228
C)0.9772
D)0.9544
E)1.0000

Question 67

Suppose a population has a mean of 90 and a standard deviation of 28.If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a mean of less than 84 is ___.

A)0.9332
B)0.0668
C)0.4332
D)0.8664
E)1.0000

Question 68

Suppose the population of all public Universities shows the annual parking fee per student is normally distributed with a mean of $110 with a standard deviation of $18.If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a sample mean between $100 and $115 is _______.

A)0.9738
B)0.4738
C)0.0262
D)0.6103
E)0.1103

Question 69

A carload of steel rods has arrived at Cybermatic Construction Company.The car contains 50,000 rods.Claude Ong, Manager of Quality Assurance, directs his crew to measure the lengths of 100 randomly selected rods.If the population of rods have a mean length of 120 centimetres and a standard deviation of 0.05 centimetres, the probability that Claude's sample has a mean less than 119.985 centimetres is ___.

A)0.9974
B)0.0026
C)0.4987
D)0.0013
E)0.0030

Question 70

Suppose a population has a mean of 90 and a standard deviation of 28.If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a mean of more than 95 is ___.

A)0.1056
B)0.3944
C)0.4286
D)0.8944
E)1.0000

Question 71

Suppose a population has a mean of 400 and a standard deviation of 24.If a random sample of size 144 is drawn from the population, the probability of drawing a sample with a mean between 393.5 and 396.5 is ___.

A)0.0802
B)0.0012
C)0.0407
D)0.0395
E)1.0000

Question 72

Suppose a population has a mean of 400 and a standard deviation of 24.If a random sample of size 144 is drawn from the population, the probability of drawing a sample with a mean of more than 404.5 is ___.

A)0.0139
B)0.4861
C)0.4878
D)0.0122
E)0.5000

Question 73

Suppose the population of all public Universities shows the annual parking fee per student is normally distributed with a mean of $110 with a standard deviation of $18.If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a sample mean between $112 and $115 is closest to _______.

A)0.9738
B)0.7777
C)0.7823
D)0.1915
E)1.7561

Question 74

Suppose a population has a mean of 870 and a variance of 1,600.If a random sample is size 64 is drawn from the population, the probability that the sample mean is between 860 and 875 is ___.

A)0.9544
B)0.6826
C)0.8785
D)0.5899
E)0.8185

Question 75

Suppose a population has a mean of 90 and a standard deviation of 28.If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a mean between 80 and 100 is ___.

A)0.9876
B)0.0124
C)0.4938
D)0.0062
E)1.0000

Question 76

Suppose a population has a mean of 870 and a variance of 8,100.If a random sample is size 36 is drawn from the population, the probability that the sample mean is between 840 and 900 is ___.

A)0.9544
B)0.6826
C)0.8185
D)0.5899
E)0.0897

Question 77

Suppose the population of all public Universities shows the annual parking fee per student is normally distributed with a mean of $110 with a standard deviation of $18.If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a mean of less than $92 is _______.

A)0.3400
B)0.1600
C)0.0000
D)1.0000
E)0.7000

Question 78

Suppose a population has a mean of 450 and a variance of 900.If a random sample is size 100 is drawn from the population, the probability that the sample mean is between 448 and 453 is ___.

A)0.4972
B)0.6826
C)0.4101
D)0.5899
E)0.9878

Question 79

A carload of steel rods has arrived at Cybermatic Construction Company.The car contains 50,000 rods.Claude Ong, Manager of Quality Assurance, directs his crew to measure the lengths of 100 randomly selected rods.If the population of rods has a mean length of 120 centimetres and a standard deviation of 0.05 centimetres, the probability that Claude's sample has a mean greater than 120.0125 centimetres is ___.

A)0.0124
B)0.0062
C)0.4938
D)0.9752
E)1.0000

Question 80

Suppose the population of all public Universities shows the annual parking fee per student is normally distributed with a mean of $110 with a standard deviation of $18.If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a mean of more than $115 is _______.

A)0.9738
B)0.4738
C)0.0262
D)0.6103
E)0.1103