### 2 Types of errors

Since we cannot be 100% sure that a hypothesis is true or false it is possible that:

- a correct hypothesis will be rejected;
- a false hypothesis will be accepted.

Rejecting a correct hypothesis is called a Type I error and accepting a false hypothesis is called a Type II error.

By working in a logical manner and developing a set of rules or guide-lines, it is possible to minimise the occurrence of such errors.

This will introduce you to the basic ideas of hypothesis testing in a non-mathematical way by using a problem solving approach to highlight the concepts as they are needed.

Once you have learned how to apply the basic ideas, you will be capable of applying hypothesis testing to a very wide range of practical problems and learning about methods of hypothesis testing which are not covered in this Workbook.