Presentation by Andreas Schleicher Tackling the School Absenteeism Crisis 30 ...
Nonprobability Sampling
1. N O N P R O B A B I L I T Y S A M P L I N G Danilo C. Olaer, Jr., R.N. Graduate Student
2. SOME TERMS TO REMEMBER . . . Sampling The process of selecting a portion of the population to represent the entire population. Element Sample The entire aggregation of cases in which a researcher is interested. The basic unit about which information is collected. A subset of population elements.
3. SOME TERMS TO REMEMBER . . . Probability Sampling Non-probability Sampling Involves random selection of elements in which each element has a chance of being selected. Involves non-random methods in the selection of elements in which not all have equal chances of being selected. Sampling Bias The over-representation or under-representation of some segment of the population in terms of a characteristic relevant to the research question. Sampling Design Used in the selection of a sample within a population intended to yield knowledge, especially for the purposes of making predictions based on statistics.
6. What are the techniques used ??? Snowball Sampling Quota Sampling Convenience Sampling Purposive Sampling
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9. A group of students in Ateneo de Davao University conduct a study about coping mechanisms of Clinical Instructors. They interview clinical instructors they knew in school, a couple of instructors who handled them in the area and few others who are known to them. C o n v e n i e n c e S a m p l i n g
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13. P u r p o s i v e S a m p l i n g Used when you want to access a particular subset of people based on purpose. Method: When taking the sample, reject people who do not fit a particular profile.
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16. P u r p o s i v e S a m p l i n g The Graduate Students want to get opinions from non-working mothers. They go around Brgy. Kalunasan knocking on doors during the day when children are likely to be at school. They ask to speak to the “woman” of the house. Their first questions are then about whether there are children and whether the woman has a day job.
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19. Q u o t a S a m p l i n g A researcher in Colon wants 100 opinions about a new color of cheese. He sets up a stall and canvasses passers-by until she has got 100 people to taste the cheese and complete the questionnaire.
20. Not used when the goal of a study is to draw empirical generalizations about a larger population or group . I n c o n c l u s i o n , Best used in “exploratory” research studies, where the goal is to gain some initial insights… Findings could be viewed as “ suggestive” - A prelude to the main study.
21. N O N – P R O B A B I L I T Y S A M P L I N G Use who is available. Get sampled people to nominate others. Select the samples based on preconceived purpose. Keep going until the sample size is reached. CONVENIENCE SNOWBALL QUOTA PURPOSIVE
