Samples

Question 1

Simple/Unrestricted Random Sampling

Answer 1

Simple random-Select people at random with no replacements
Unrestricted random- Select people at random with replacements
Advantages-
Will always give a random sample✅
No bias in the sampling method ✅
Disadvantage-
Can take a long time ❌
Can be very expensive❌
You need a list of all members in a ❌population
You may not be able to use all members of a population ❌
Some members selected for the sample may not be useful❌

Question 2

Simple Random Sample

Answer 2

It is a random sample where members of the population are selected for the sample without replacement.
To do it:
Assign all [members] of [ the population] with a number from 1 to [ population size]
Use random number generator to generate [sample size] random numbers between 1 and [population size]

Question 3

Proportional Stratified Sample

Answer 3

Picking people from all groups of interest so the sample represents the population
Fair representation ✅
Need to know exact population ❌

Question 4

Snowball sample

Answer 4

When you pick a few people at random and they pick the rest of the sample
Lots of data for minimal work ✅
Biased ❌

Question 5

Cluster Sample

Answer 5

Selecting people at random from smaller groups of convenience
More convenient✅
Time consuming ❌

Question 6

Judgemental sample

Answer 6

When you pick people based on a set of criteria
Easy/Cheap/relevant ✅
Biased❌

Question 7

Systematic sample

Answer 7

When you put 1 person at random, and every nth person after that
easy✅
depends on context❌