BUEC 232 Lecture Notes - Lecture 6: Standard Deviation, Statistical Significance, Type I And Type Ii Errors

• School: Simon Fraser University
• Department: Business Economics
• Course: BUEC 232
• Professor: George Zhang

Document Summary

Want to draw conclusions based on sample data i. e. -- say something about an entire population based on information in a sample. We want to quantify the margin of error we are likely to encounter. Examples: i"m interested in estimating the mean income of loggers in a state, gallup poll. Our goal is to obtain an estimate of some parameter of a population. We want our estimate will be of the general form. To get our estimate, we take a random sample from the population and proceed on the basis of the information we obtain from the sample. Our best guess is xbar, the sample mean. To determine estimation error, we"ll use our knowledge of sampling distribution of xbar. We know that xbar has mean , with standard deviation, /sqrt(n), where n is our sample size. If our original population is normal, we also know that xbar is normally distributed.