# ztest

Hypothesis test for the mean of a sample with known standard deviation.

## Syntax

[h,pvalue,ci] = ztest(x,m,sigma)

[h,pvalue,ci] = ztest(x,m,sigma,name,value)

## Inputs

`x`- Data sample to be tested.
`m`- Hypothesis mean.
`sigma`- Populations standard deviation.
`name`- Name of an option whose value follows. Multiple name/value pairs are allowed. The supported options are alpha and dim.
`value`- Value for the preceeding option name.

## Outputs

- h
`0`if the null hypothesis is accepted.`1`if the null hypothesis is rejected.- pvalue
- The p-value of the test.
- ci
- A 100*(1-alpha)% confidence interval for the population mean.

## Example

Vector ztest example

```
x = [7.3 9.4 5.9 6.5 5.5 7 5.3 7.3 2.6 8.7 8.1 2.5 3.9 1.4 0.2 4 6 6.1 10.3 1.2];
[h,pvalue,ci] = ztest(x,5,2)
```

```
h = 0
pvalue = 0.30367
ci = [Matrix] 1 x 2
4.5835 6.3365
```

## Comments

ztest is a 1 sample z test and assumes that the sample comes from a normally distributed population. The null hypothesis is that the hypothesized mean is the population mean.