STAT 1430 Study Guide - Midterm Guide: Probability Density Function, Sample Space, Stratified Sampling

68 views3 pages
violetdog372 and 175 others unlocked
STAT 1430 Full Course Notes
STAT 1430 Full Course Notes
Verified Note
25 documents

Document Summary

Data collection: two ways of collecting data: observational studies and experiments, random sample: each group of the same size has the same likelihood/chance/probability of being selected as the sample. There are two main types of random samples - simple random sample and stratified random sample. sampling procedure and the sample must represent the entire population: bias is a main concern when sampling. To avoid biased sample, we must use a: examples of biased sample: convenience, volunteer (self-selected), undercoverage, several important concepts in experimental designs: independent variables (factors); Dependent variables (responses): treatment group and control group. Two types of variables: quantitative data and categorical data; Data distribution: shape, center, skewness, and variability; Descriptive statistics: suppose we have x1, , xn observations. The sample standard deviation always has the same unit as the original data; it can never be negative; it can equal to 0; it is affected by outliers and skewness; interquartile range (iqr):