chapter 8 - Handout 10.Inferences in large samples. Chapter...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Statistical inference -drawing conclusions about population parameters from an analysis of the sample data. Types of inference : 1. estimation of parameter(s) -obtain an estimate of the unknown true value along with a determination of its accuracy. a) estimate a single value for the unknown parameter-a point estimate b)determine an interval of plausible values for the unknown parameter- a confidence interval 2. testing of statistical hypotheses -to examine whether the sample data support or contradict the statement about the true value of the parameter. Handout 10.Inferences in large samples. Chapter 8 (8.1-8.3 ) Confidence interval for a population mean. Terminology Parameter : µ or p, the average or the proportion in the population. Estimator (point estimator) : The sample mean or the sample proportion (a general formula,statistic). Estimate (point estimate ) :a number determined from a sample that is used to estimate the corresponding population parameters. Sampling error -the difference between a value (a statistic) computed from a sample and the value of a parameter. Since we seldom know the value of a parameter ,we do not know exactly the size of the sampling error. Standard error S.E – the standard deviation of an estimator Point and Interval Estimates •A point estimate is a single number. confidence interval is based on one sample,but takes into consideration a variation from sample to sample, gives information about closeness to unknown population parameters- stated in terms of level of confidence ,but never 100% confidence.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

chapter 8 - Handout 10.Inferences in large samples. Chapter...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online