RelativeResourceManager-2

RelativeResourceManager-2 - Sampling Distributions Central...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon

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

View Full DocumentRight Arrow Icon

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

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

Unformatted text preview: Sampling Distributions Central Limit Theorem PSY 2801: Summer 2010 Sampling Distributions Jeff Jones University of Minnesota Jeff Jones Ch 8 Sampling Distributions Central Limit Theorem Sampling Distributions A Sampling Distribution is a distribution of a statistic . If we take one person from a distribution of heights, they most likely will not be equal to the population average height; if we take a finite sample of people from a distribution, their average will probably not equal the population average either. Jeff Jones Ch 8 Sampling Distributions Central Limit Theorem Sampling Dist of the Mean We will focus on the sampling distribution of ¯ x , as that is the most common sampling distribution. Staying with our height example, suppose we wanted to find out the mean height of American men 1 American men is our well-defined population of interest 2 μ of height is our parameter of interest Parameter of Interest : The parameter you’re attempting to make conclusions about for your population. Jeff Jones Ch 8 Notes Notes Notes Sampling Distributions Central Limit Theorem Sampling Dist of the Mean So, to get an idea of mean male height from the population, we take a random sample of 9 American men, measure them on height, and take their mean. But there’s a difference between a statistic and a parameter (we only have a statistic), so we decide to take another random sample of 9 American men, measure them on height, and take their mean. Jeff Jones Ch 8 Sampling Distributions Central Limit Theorem Sampling Dist of the Mean Since there’s a discrepancy between our first sample mean and our second sample mean, we decide to take another sample to settle the score. Random Sample of 9 American men Calculate Height Take Mean But each sample mean is a little different than every other sample mean → why is this happening? Jeff Jones Ch 8 Sampling Distributions Central Limit Theorem Sampling Dist of the Mean Standard Error : The standard deviation of a sampling distribution If we took a regular distribution, we would have a range of values for people; with a sampling distribution we would have a range of values for means. It is what we would expect to obtain for a statistic! If we are trying to estimate a parameter, we would say that the variation of means is due to sampling error . Sampling error is very important → it is what we are trying to estimate in order to make conclusions about parameters for the rest of the semester. Jeff Jones Ch 8 Notes Notes Notes Sampling Distributions Central Limit Theorem Sampling Distributions These are the steps to obtaining a sampling distribution: 1 Pick a population of interest, a statistic, and a sample size ( N ) 2 Randomly sample N observations from the population of interest 3 Calculate the statistic on those N observations 4 Throw everybody back into the pool 5 Repeat steps 2-4 an infinite number of times 6 Plot the means, calculate statistics on the means An important point to note is that a sampling distribution is...
View Full Document

This note was uploaded on 10/08/2010 for the course PSY 2801 taught by Professor Guyer during the Summer '08 term at Minnesota.

Page1 / 12

RelativeResourceManager-2 - Sampling Distributions Central...

This preview shows document pages 1 - 4. Sign up to view the full document.

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