Manuals/calci/ZTEST

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ZTEST(ar,x,sigma)


  • is the array of values.
  • is the value to test.
  • is the standard deviation of the population.


Description

  • This function gives the one-tailed probability of z-test.
  • Z-test is used to determine whether two population means are different when the variances are known and the sample size is large.
  • In , is the array of values against which the hypothesized sample mean is to be tested.
  • is the hypothesized sample mean, and is the standard deviation of the population.
  • When we are not giving the sigma value, it will use the standard deviation of sample.
  • This function returns the probability that the supplied hypothesized sample mean is greater than the mean of the supplied data values.
  • The test statistic should follow a normal distribution.
  • ZTEST is calculated when sigma is not omitted and x=μ0 : Failed to parse (syntax error): {\displaystyle ZTEST(ar,\mu_0,sigma)=1-NORMSDIST((\bar{x}-μ0)/\frac{sigma}{\sqrt{n}})} .
  • ZTEST is calculated when sigma is omitted and x=μ0:

Failed to parse (syntax error): {\displaystyle ZTEST(ar,μ0)=1-NORMSDIST((\bar{x}-μ0)/\frac{s}{\sqrt{n}})} where is sample mean , is the sample deviation and is the size of the sample.

  • Suppose we want to calculate the z-test for two tailed probability then this can be done by using the Z.Test function: .
  • This function will give the result as error when
    1. Any one of the argument is non-numeric.
    2. ar or x is empty.
    3. ar contains only one value.