# Statistics 3

HideShow resource information
• Created by: Caraa
• Created on: 20-06-13 19:41
Simple random sampling
Is where a sample is selected from a population and each individual is chosen by chance and so has an equal chance of being included in the sample.
1 of 12
Stratified sampling
Where samples are taken from sub groups of the population as different groups have different opinions
2 of 12
Cluster sampling
Where the entire population is split into groups and a random sample of these groups is selected
3 of 12
Independant sampling
Samples selected from the same population or different populations which have no effect on each other
4 of 12
Random sampling
Where a sample is selected from a population and each individual is chosen by chance but the chances of a person being included in the sample is not necessarily equal.
5 of 12
Quota sampling
When samples are selected depending on what the sampling is for. Eg an interviewer going out and choosing people
6 of 12
Systematic sampling
Where samples are chosen in a systematic way eg each 10 people
7 of 12
What are the requirments of a sample
Unbiased and representative of the whole population
8 of 12
Why would you take a sample
If the population is too large or the sampling process is destructive
9 of 12
What is a 95% confidence interval
In repeated sampling, 95% of confidence intervals constructed in this way will contain the true population mean
10 of 12
What is meant by a 5% confidence level?
The probability of rejecting H0 if it is true is 0.05
11 of 12
An outlier will be
2 SD away from the mean. UQ (0.25)+1.5 x IQR
12 of 12

## Other cards in this set

### Card 2

#### Front

Stratified sampling

#### Back

Where samples are taken from sub groups of the population as different groups have different opinions

Cluster sampling

### Card 4

#### Front

Independant sampling

Random sampling