Statistical hypothesis test is one of the true positive tests. A statistical test method is similar to a trial. Here are two hypotheses H_{0} and
H_{1}.The initial one is call **null hypothesis**, along with for the time being accepted. The next one is called alternative hypothesis. During a statistical hypothesis
test, there are two types of wrong conclusions that can be drawn. They are **type I error and type II error.**

A Type I error occur while the researcher rejects a null hypothesis while it be true. The probability of
commit a Type I error is call the **significance level**. This probability be as well called **alpha**, along with is frequently denoted through α.

**What is meant for Type II error**.

A Type II error occurs while the researcher fail to reject a null hypothesis to is false. The probability of
commit a Type II error is call **Beta**, along with is often denoted through β. The probability of not committing a Type II error is calling the **Power** of the
test.

**Example 1 for what is true positive:**

In a sample of size 17 drawn from a normal population standard deviation is 3 can you say that population standard deviation is 4.

**Procedure:** Null hypothesis:

H_{0}:The population standard deviation is 4

**Test statistic:**

`chi^2=(ns^2)/(sigma^2)` , `chi^2(n-1)`

**Level of significance:**

α=0.05 at g% level of `chi^2`table value for 16 degrees of freedom is 26.3

**Calculation:**

n=17,s=3,sigma=4

`chi^2=(17xx9)/(16)`

=153/16

=9.5625

Calculated value = 9.5625

Table value = 26.3

Calculated value < Table value

Null hypothesis is accepted.

The population of standard deviation is 4

**Result:** The population standard deviation is 4

**Example 2:(what is true positive)**

In a sample of size 17 drawn from a normal population standard deviation is 6 can you say that population standard deviation is 4.

**Procedure:** Null hypothesis

H_{0}:The population standard deviation is 4

**Test statistic:**

`chi^2=(ns^2)/(sigma^2)` `chi^2(n-1)`

**Level of significance:**

α = 0.05 at g% level of `chi^2`table value for 16 degrees of freedom is 26.3

Calculation:

n = 17,s = 3,sigma = 4

`chi^2=(17xx36)/(16)`

= `612/16`

= 38.25

Calculated value = 38.25

Table value = 26.3

Calculated value > Table value

Null hypothesis is not accepted.

**Result:** The population standard deviation is not 4.