HSS 2381: lecture 6

Means

Two forms of statistical inference

– Hypothesis testing

– Confidence interval estimation

What is a Hypothesis?

• A hypothesis is an assumption about the population parameter

• The parameter must be identified before analysis.

The Null Hypothesis, H0

• States the Assumption to be tested

• Begin with the assumption that the null hypothesis is TRUE.

• Hypothesis testing will enable you to determine whether The Null Hypothesis may or may not be rejected.

The Alternative Hypothesis, HA (H1 )

Is the opposite of the null hypothesis

Identify the Problem

• State the Null Hypothesis

• State its opposite, the Alternative Hypothesis

Type 1 error

• when the null hypothesis is rejected when its true

Type 2 error

• when the null hypothesis is not rejected when it is false

Level of significance

3 types of tests

• left tailed

• right tailed

• two tailed test

Z-Test Statistic to decide on Ho

Test Statistic large samples n≥30