Textbook Notes (368,413)
York University (12,845)
Psychology (3,584)
PSYC 2530 (29)
Chapter 7

# Ch. 7 - Probability and Samples.docx

2 Pages
95 Views

School
Department
Psychology
Course
PSYC 2530
Professor
Anne Russon
Semester
Fall

Description
Ch. 7 - Probability & Samples Sunday, November 11, 2012 5:54 PM PSYC 2530 Introductory Statistics Chapter 7: Probability and Samples: The Distribution of Sample Means  Sample error is the natural discrepancy, or amount of error, between a sample statistic and its corresponding population parameter.  The distribution of sample means is the collection of sample means for ALL of the possible random samples of a particular size (n) that can be obtained from a population.  A sampling distribution is a distribution of statistics obtained by selecting all of the possible samples of a specific size from a population.  Characteristics of a distribution of all sample means: o 1) The sample means should pile up around the population means o 2) The pile of sample means should tend to form a normal-shaped distribution o 3) In general, the larger the sample size, the closer the sample means should be to the population mean, μ  In a distribution of sample means: o Mean = μ o  Central Limit Theorem: For any population with mean μ and standard deviation σ, the distribution of sample means for sample size n will have a mean of μ and a standard deviation of nand will approach a normal distribution as n approaches infinity. o 1) The central limit theorem describes the distribution of sample means for any population, no matter what shape, mean, or standard deviation. o 2) The distribution of sample means “approaches” a normal distribution very rapidly. By the time the sample size reaches n = 30, the distribution is almost perfectly normal.  According to the central limit theorem, the parameters of the distribution of sample means are as follows: o a. Shape. The distribution of sample means is normal if EITHER of the following is satisfied:  1) The population from which the samples are selected is a normal distribution  2) The number of scores (n) in each samp
More Less

Related notes for PSYC 2530
Me

OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Join to view

OR

By registering, I agree to the Terms and Privacy Policies
Just a few more details

So we can recommend you notes for your school.