01:960:285 Lecture Notes - Lecture 2: American Community Survey, Randomized Controlled Trial, Selection Bias

• School: Rutgers University
• Department: Statistics and Biostatistic
• Course: 01:960:285
• Professor: Zhanyun Zhao

Document Summary

Stat 285- lecture 2- data collection methods: data collection, critical part of conducting study, secondary sources of data. Statistical data collection based on preexisting conveniences: data from a survey, sampling a group of people and recording the response, examples: political polls, american community survey, types of survey, questionnaires, multimode. Interview: when one utilizes both previous methods for a survey, observational study, observe experimental units and record variables of interest, examples:classroom observations, traffic, can observe openly or hidden, sampling: If clearly observing, presence could possibly bias or skew results: one can"t get data of whole population, easier to get representative sample. Individuals selected are representative of a large population in terms of key characteristics. True representation is very difficult: biased samples can result if one inadvertently samples a less representative subset of the population. Example: sampling biz class out of entire university: sampling design. Simple probability sampling: random sample, systematic sample.