Term

Definition
As sample size gets large enough, sampling distribution is approximately normal. This is true regardless of the dist. of indiv. values. At least 30 values. 


Term

Definition
Dividing the N items in the frame into several clusters so that ceach cluster is representative of the entire population. Clusters are natrually occurring designations, such as counties, election districts, city blocks, households, or sales territories. 


Term

Definition
If certain groups of items are excluded from the frame so that they can have no chance of being selected in the sample. Results in selection bias. 


Term

Definition
A listing of the items that make up the population 


Term

Definition
Getting the opinions of preselected experts in the subject matter 


Term

Definition
Such as ambiguous wording, Hawthorne effect, and respondent error. 


Term

Definition
Failure to collect data on all items in the sample and results in a nonresponse bias. 


Term
Sampling distribution of the mean 

Definition
The distribution of all posssible sample means if you select all possible samples of a given size 


Term
Sampling distribution of the proportion 

Definition
Follows the binomial distribution. You can use normal distribution to approx. the binomial when n*pi and n(1pi) are each at least 5. 


Term

Definition
Reflects the variation or "chance differences" from sample to sample. 


Term

Definition
The mean of all the possible sample means (of a given sample size, n) is equal to the population mean 

