Permutations

Before jumping into this testing analysis, we will review some basic knowledge of permutations and combinations.

Permutations and combinations

Permutations and combinations are two mathematical techniques for taking a set of objects to create subsets from a population but in two different ways. The order of objects matters in permutations but does not matter in combinations.

In order to understand these concepts easily, we will consider two examples. There are 10 people at an evening party. The organizer of the party wants to give 3 prizes of $1,000, $500, and $200 randomly to 3 people. The question is how many ways are there to distribute the prizes? Another example is that the organizer will give 3 equal prizes of $500 to 3 people out of 10 at the party. The organizer really does not care which prize is given to whom among the 3 selected people. Huy, Paul, and Stuart are our winners in these two examples but, in the first example, different situations may play...