Z.TEST function

Z.TEST (Values, X, Sigma?) Z.TEST (Values; X; Sigma?)

Values

The values containing a sample from the population (which is assumed to have a normal distribution).

X

Number Number

The value to test.

Sigma

Number Number (optional)

The known standard deviation of the population. If omitted, the sample standard deviation is used.

Returns

Number Number

The one-tailed cumulative probability value of a Z-test.

Returns the one-tailed cumulative probability value of a Z-test. This is the probability that the mean of a sample drawn from a population with the mean given by the X parameter is at least as large as the mean of the given values. For a two-tailed probability, use this formula:

2 * MIN ( Z.TEST (Values, X, Sigma), 1 - Z.TEST (Values, X, Sigma))

2 * MIN ( Z.TEST (Values; X; Sigma); 1 - Z.TEST (Values; X; Sigma))

Examples

Z.TEST ({ 5, 5.9, 4.1, 7.3, 2.8, 1.2, 6 }, 8, 10)

Z.TEST ({ 5; 5,9; 4,1; 7,3; 2,8; 1,2; 6 }; 8; 10)

Returns roughly 0.81.

2 * MIN ( Z.TEST (Values, X, Sigma), 1 - Z.TEST (Values, X, Sigma))

2 * MIN ( Z.TEST (Values; X; Sigma); 1 - Z.TEST (Values; X; Sigma))

Returns roughly 0.37, the two-tailed probability value of a Z-test for the same values.