HLTB15H3 Lecture Notes - Lecture 7: Sampling Frame, Population Study, Sample Size Determination
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Disadv: only find about sample, and estimate for population. Basically continue sampling as long as you make new findings. When no new findings, it"s called saturation point. There is going to be diff between sample stats and population mean. *true population mean - the true mean of entire population. The difference is in relation to sample units. As sample size increases, more accuracy between sample stats and true pop mean. The greater diff in variable, greater diff between sample stats and pop mean. Really young and really old in class, it"s going to be so off. Have equal and independent chance of being chosen. Randomly select certain column and row or something. Sampling error can be reduced if heterogeneity can be reduced. Proportionate: # from each stratum is proportion to total pop. More heterogeneity, more respondents needed a lot of diff, need large sample size.