$$\bar { x } _ { 1 } - \bar { x } _ { 2 } \text { is an unbiased statistic used to estimate } \mu _ { 1 } - \mu _ { 2 } \text {. }$$

question 14

True/False

$$\bar { x } _ { 1 } - \bar { x } _ { 2 } \text { is an unbiased statistic used to estimate } \mu _ { 1 } - \mu _ { 2 } \text {. }$$ $$\text { For two independent samples, } \sigma _ { \bar { x } _ { 1 } - \bar { x } _ { 2 } } = \sqrt { \frac { \sigma _ { 1 } ^ { 2 } } { n _ { 1 } } - \frac { \sigma _ { 2 } ^ { 2 } } { n _ { 2 } } } \text {. }$$

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Definitions:

Test Statistic

A calculated value used to make a decision regarding a hypothesis test; it measures the degree of agreement between a sample data and the null hypothesis.

Sample Proportion

The ratio of members in a statistical sample that have a particular attribute to the total number of members in the sample.

Null Hypothesis

The null hypothesis is a statement used in statistics that proposes there is no significant difference or effect, serving as the starting point for hypothesis testing.

Alternative Hypothesis

A statistical hypothesis that proposes a difference or effect, contrasting the null hypothesis.