TINV spread function returns the two-tailed inverse of the Student's t-distribution.

__SYNTAX:__

TINV(probability,degrees of freedom)

Probability: The associated probability for the two-tailed Student's t-distribution. The following probabilities are supported:

Probability |
Cum. Prob |
Confidence Level |

0.50 |
t.75 |
50% |

0.40 |
t.80 |
60% |

0.30 |
t.85 |
70% |

0.20 |
t.90 |
80 |

0.10 |
t.95 |
90% |

0.05 |
t.975 |
95% |

**0.02** |
**t.99** |
**98%** |

0.01 |
t.995 |
99% |

0.002 |
t.999 |
99.8% |

0.001 |
t.9995 |
99.9% |

Degrees of freedom: The degrees of freedom with which to characterize the distribution. A whole number between 1 and 100. All numbers greater than 100 return the Z value.

__EXAMPLES:__

Calculate the Student's t-value when calculating a Lab MDL based on 7 samples. Use the 0.02 Probability (98% confidence level) and 6 degrees of freedom(n-1).

=TINV(0.02,7-1) returns 3.14267