A pollster wants to obtain a large sample of voters with the ...

[V@ndy87]

A pollster wants to obtain a large sample of voters with the least amount of trouble. Each subject is asked to complete a pencil-paper questionnaire containing seven multiple-choice questions.
 
  Each person completing the survey receives a 1-off coupon for a population coffee chain. The pollster decides to stand outside twenty different supermarkets for four hours each and ask patrons to participate in the research. Which method of sampling is this?
  a. Network or snowball sampling
  b. Purposive sampling
  c. Convenience sampling
  d. Cluster sampling

Question 2

Five hundred persons were chosen to participate, 270 women and 230 men, representative of the population of Portland, Oregon, treated for congestive heart failure at one of its four main hospitals.
 
  Patients were selected using a table of random numbers, from a master list of all patients who had been treated for CHF in the previous three months. This is an example of what type of sampling strategy?
  a. Simple random sampling
  b. Convenience sampling
  c. Purposive sampling
  d. Stratified random sampling

[6ana001]

Answer to Question 1

ANS: C
Convenience sampling involves the nonrandom selection of subjects who meet criteria and are available and willing to be in the study, or basically subjects who are in the right place at the right time. Thus, this is the easiest, most economic method to obtain a large sample. In purposive sampling, sometimes referred to as purposeful, judgmental, or selective sampling, the researcher consciously selects certain participants, elements, events, or incidents to include in the study. In purposive sampling, qualitative researchers select information-rich cases, or those cases that can teach them a great deal about the central focus or purpose of the study. This is almost exclusively a qualitative sampling strategy. Network or snowball sampling takes advantage of social networks to recruit subjects and is almost exclusively a qualitative sampling strategy. Cluster sampling is a type of random sampling.

Answer to Question 2

ANS: D
Stratified random sampling is used when the researcher knows some of the variables in the population that are critical to achieving representativeness. Variables commonly used for stratification are age, gender, ethnicity, socioeconomic status, diagnosis, geographical region, type of institution, type of care, care provider, and site of care. The variable or variables chosen for stratification need to be correlated with the dependent variables being examined in the study. Subjects within each stratum are expected to be more alike (homogeneous) in relation to the study variables than they are to be like subjects in other strata or the total sample. In stratified random sampling, the subjects are randomly selected on the basis of their classification into the selected strata.

[V@ndy87]

TY

[6ana001]

Happy to Help