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TOOLS > STATISTICS > VECTOR > T TEST

PURPOSE Performs a t-test with a significance based upon a permutation test.

DESCRIPTION Undertakes a standard t-test to compare the means of two groups but uses a permutation test to generate the significance level so that standard assumptions on independence and random sampling are not required.   

PARAMETERS 
   
Dependent (Y) variable:
Name of file containing the dependent vector, this must be a UCINET data file. Enter the filename followed by ROW (or COL) and a number to specify which row or column of the file to use.

Independent (X) variable:
Name of file containing the independent vector, this must be a UCINET data file. Enter the filename followed by ROW (or COL) and a number to specify which row or column of the file to use.

Number of random permutations: (Default = 5000)
The larger the number of permutations, the better the estimates of standard error and "significance", but the longer the computation time.

Random number seed:
The random number seed sets off the random permutations.  UCINET generates a different random number as default each time it is run.  This number should be changed if the user wishes to repeat an analysis.  The range is 1 to 32000.

  
LOG FILE Gives standard statistics on each group followed by significance tests. The difference in means is reported together with the two one tailed tests assessing whether one mean is greater than the other and the two tailed test.

TIMING N/A

COMMENTS None

REFERENCES None