Tham khảo tài liệu 'giáo trình marketing nghiên cứu - phần 12', kinh doanh - tiếp thị, tiếp thị - bán hàng phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Determining How to Select a Sample Basic Concepts in Sampling Population: the entire group under study as defined by research objectives Researchers define populations in specific terms such as “heads of households located in areas served by the company who are responsible for making the pest control decision.” Ch 12 Basic Concepts in Sampling Sample: a subset of the population that should represent the entire group Sample unit: the basic level of investigation Census: an accounting of the complete population Ch 12 Basic Concepts in Sampling Sampling error: any error in a survey that occurs because a sample is used A sample frame: a master list of the entire population Sample frame error: the degree to which the sample frame fails to account for all of the population a telephone book listing does not contain unlisted numbers Ch 12 Reasons for Taking a Sample Practical considerations such as cost and population size Inability of researcher to analyze huge amounts of . | Determining How to Select a Sample Basic Concepts in Sampling Population: the entire group under study as defined by research objectives Researchers define populations in specific terms such as “heads of households located in areas served by the company who are responsible for making the pest control decision.” Ch 12 Basic Concepts in Sampling Sample: a subset of the population that should represent the entire group Sample unit: the basic level of investigation Census: an accounting of the complete population Ch 12 Basic Concepts in Sampling Sampling error: any error in a survey that occurs because a sample is used A sample frame: a master list of the entire population Sample frame error: the degree to which the sample frame fails to account for all of the population a telephone book listing does not contain unlisted numbers Ch 12 Reasons for Taking a Sample Practical considerations such as cost and population size Inability of researcher to analyze huge amounts of data generated by census Samples can produce precise results Ch 12 Two Basic Sampling Methods Probability samples: ones in which members of the population have a known chance (probability) of being selected into the sample Non-probability samples: instances in which the chances (probability) of selecting members from the population into the sample are unknown Ch 12 Probability Sampling Methods Simple random sampling Systematic sampling Cluster sampling Stratified sampling Ch 12 Probability Sampling Methods Ch 12 Probability Sampling: Simple Random Sampling Simple random sampling: the probability of being selected into the sample is “known” and equal for all members of the population ., Blind Draw Method Random Numbers Method (see MRI , p. 335) Ch 12 Probability Sampling: Simple Random Sampling Advantage: Known and equal chance of selection Disadvantages: Complete accounting of population needed Cumbersome to provide unique designations to every population member
