Systematic Sampling

Lets consider you want to sample 6 items from a sequential list of 30
30/ 6 = 5
You could easily just select every 5th item
In a random sample every member of the population has an equal chance of being chosen.
In practice systematic sampling is almost accepted as being random.

Advantages

1) Very quick and efficient to conduct
2) Spreads the sample more evenly over the population
3) Easier to conduct than a simple random sample

Disadvantages

1) There may be a hidden pattern associated with the population.

The term systematic refers to the fact that the population has been numbered using an appropriate system