Question 1

With a nonprobability sample,the researcher has some savings in cost and/or time but at the expense of using a sample that is not truly representative of the population.

Accepted Answer

Nonprobability sampling methods do not involve random selection of participants and therefore may not accurately reflect the characteristics of the population being studied. However, they can be less costly and time-consuming than probability sampling methods.

Question 2

Stratified sampling results in a more accurate overall sample by allowing for explicit analysis of each stratum and by allowing the estimation of the overall sample mean by use of a weighted measure.

Accepted Answer

Stratified sampling is designed to improve the accuracy of a sample by ensuring that each stratum, or subset of the population, is represented in proportion to its size. This allows for more explicit analysis and weighting of each stratum, ultimately resulting in a more accurate overall sample estimate.

Question 3

There are two practical applications in which simple random sample designs are employed quite successfully: random digit dialing and computer-based random samples.

Accepted Answer

Random digit dialing and computer-based random samples are both widely used and effective ways of obtaining simple random samples.

Question 4

With simple random sampling,the probability of being selected into the sample is unequal for all members of the population.

Accepted Answer

With simple random sampling, each member of the population has an equal probability of being selected into the sample. Therefore, the statement provided is false.

Question 5

In systematic sampling,the researcher decides on a skip interval,which is calculated by dividing the number of names on the list by the sample size.

Accepted Answer

In systematic sampling, the skip interval is indeed calculated by dividing the population size by the sample size.

Question 6

To use systematic sampling,it is not necessary to have a complete listing of the population.

Accepted Answer

Systematic sampling requires a complete listing of the population to select samples at regular intervals, ensuring each member has an equal opportunity to be chosen.

Question 7

Systematic sampling can be applied with less difficulty and accomplished in a shorter time than can simple random sampling

Accepted Answer

Systematic sampling involves selecting every nth item from a population, which can be done quickly and easily with a predetermined sequence or formula. In contrast, simple random sampling requires selecting items completely at random, which can be more time-consuming and may require a larger sample size for accurate results. Therefore, systematic sampling can be a more efficient method.

Question 8

The random device method involves using an apparatus or a procedure to ensure that every member of the population has the same chance of being selected into the sample.

Accepted Answer

The statement accurately describes the random device method.

Question 9

Systematic sampling is more efficient than simple random sampling because only one or a very few random numbers need to be drawn at the beginning.

Accepted Answer

In systematic sampling, we select every nth individual from a population, which means we do not need to draw a random sample for every individual. Instead, we only need to select the first individual randomly, and then select the rest of the sample systematically. This makes the process more efficient and less time-consuming than simple random sampling, where every individual needs to be selected randomly.

Question 10

Systematic sampling is probability sampling because it employs a non-random starting point,which ensures there is sufficient randomness in the systematic sample to approximate an equal probability of any member of the population being selected into the sample.

Accepted Answer

Systematic sampling is considered a probability sampling method, but the statement is incorrect in saying it employs a non-random starting point to ensure randomness. The randomness in systematic sampling comes from randomly selecting the starting point, and then every nth element is chosen. The method assumes each member has an equal chance of selection only if the list does not have a pattern that might bias the selection.

Question 11

Cluster sampling is desirable when highly similar groups can be easily identified,such as subdivisions spread across a wide geographic area.

Accepted Answer

Cluster sampling is a sampling method where the population is divided into groups or clusters, and a random sample of clusters is selected. It is desirable when the clusters are similar to each other and are spread across a wide geographic area. Therefore, the statement is true.

Question 12

The terms known and unknown are misleading;to calculate a precise probability,one would need to know the exact size of the population,and it is impossible to know the exact size of the population in most marketing research studies.

Accepted Answer

Knowing the exact size of the population is necessary to calculate precise probabilities in marketing research studies. As it is almost impossible to know the exact size of the population, the terms known and unknown can be misleading in such cases.

Question 13

Convenience samples can be seriously misleading since with nonprobability sampling,there is a good possibility that non-representative sample units will be selected.

Accepted Answer

Convenience sampling involves selecting individuals who are easily accessible and available, rather than through a random selection process. This can lead to a biased sample that is not representative of the larger population, making the results unreliable and potentially misleading.

Question 14

Computer programs can be designed to generate numbers without any systematic sequence to the numbers whatsoever.This describes the random numbers method.

Accepted Answer

Random number generation does not follow any systematic sequence and can be achieved through computer programs.

Question 15

Although scientifically sound,systematic sampling does not accomplish the same end as simple random sampling,and is less efficient.

Accepted Answer

Systematic sampling can achieve similar objectives as simple random sampling by selecting samples at regular intervals from a list, and under certain conditions, it can be as efficient or even more efficient in terms of ease of implementation and data collection.

Question 16

Area sampling is a form of cluster sampling and uses a two or three-step approach.

Accepted Answer

The answer of Area sampling is a form of cluster...

Question 17

Despite some advantages,systematic sampling does not have the potential to create a sample in quality to samples created from simple random sampling.

Accepted Answer

Systematic sampling relies on selecting every nth member of the population, which can introduce bias if the selection interval aligns with any patterns or cycles within the population. Simple random sampling, while more difficult to execute, ensures that every member of the population has an equal chance of being selected and thus creates a higher quality sample.

Question 18

Cluster sampling is better suited than other probability sampling methods for populations that are not distributed in a bell-shaped pattern.

Accepted Answer

Cluster sampling is chosen for practicality and efficiency, especially when the population is large and geographically dispersed, not based on the distribution shape of the population.

Question 19

A skewed population has a long tail on one side and a short tail on the opposite end,and deviates greatly from the bell-shaped distribution that is assumed to be the case in the use of simple random,systematic,or cluster sampling.

Accepted Answer

The answer of A skewed population has a long tail...

Question 20

The simple random sampling method does not guarantee that every member of the population has an equal chance of being selected into the sample;therefore,the resulting sample,no matter what the size,will not be a valid representation of the population.

Accepted Answer

The statement is false. Simple random sampling method ensures that every member of the population has an equal chance of being selected into the sample. This is why it is considered as a valid method for sampling.

Quiz 9: Selecting the Sample