EP TT - T test

(2/27/96)

PURPOSE

Computes the t-test values for pairs of points from two average images/volumes resulting from adding two image/volume series.

SEE ALSO

AS R [Average image/volume series, optional subset]
EP [Error Probability]
EP TM [T test - Each Point]

USAGE

.OPERATION: EP TT

.FIRST AVERAGE FILE: AVE001
[Enter the name of the file containing the average of first image series. This is obtained by using operation 'AS R'.]

.FIRST VARIANCE FILE: VAR001
[Enter the name of the file containing the variance of first image series. This is obtained by using operation 'AS R'.]

.NUMBER OF IMAGES AVERAGED: 56
[Enter the number of images added when the first average image was formed.]

.SECOND AVERAGE FILE: AVE001
[Enter the name of the file containing the average of second image series. This is obtained by using operation 'AS R'.]

.SECOND VARIANCE FILE: VAR001
[Enter the name of the file containing the variance of second image series. This is obtained by using operation 'AS R'.]

.NUMBER OF IMAGES AVERAGED: 56
[Enter the number of images added when the second average image was formed.]

.SIGNIFICANCE IMAGE: SIG001
[Enter the name of the file which will contain the statistical significance of the point-by-point differences.]

NOTES

  1. For an elementary introduction into theory of statistical inference, see (e.g.) P. Armitage, "Statistical Methods in Medical Research", Blackwell Scientific Publications, p99ff.

  2. Since the correct normalization of EM images is usually unknown the results of t-test should be taken with a grain of salt.

  3. Implemented by: P. Penczek.

SUBROUTINES

TTEST

CALLER

CONF1