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help for ^discrim^                                                    (STB-x)
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Dichotomous Discriminant Analysis
---------------------------------
 
  ^discrim^ grpvar [varlist] [^, p^redict^ a^nova^ g^raph^ d^etail^ k^eep]

Description
-----------
^discrim^ allows the user to perform a discriminant analysis on a Bernoulli
distributed response of grouping variable (1/0).

Output includes table with the following statistics and their global 
designation for post-estimation use when applicable:
 
    1. Observations    [S_E_obs]       2. Independent vars  [S_E_var] 
    3. Obs: group==0   [S_E_ob0]       4. Obs: group==1     [S_E_ob1]
    5. Centroid 0      [S_E_cn0]       6. Centroid 1        [S_E_cn1]
    7. Grand centroid  [S_E_cng]       8. R-square          [S_E_r2]
    9. Mahalanobis     [S_E_mah]      10. Eigenvalue        [S_E_eig]
   11. Canon. Correl   [S_E_cc]       12. Eta squared       [S_E_e2]   
   13. Wilk's lambda   [S_E_lam]      14. Chi-square        [S_E_chi]

Output also includes a table displaying both the Discriminant Function and
Unstandardized Coefficients.

Cases in which a variable has a missing value are dropped from estimation.
The ^keep^ command does not restore such cases to active memory.

Options
-------
^predict^ provides a confusion matrix of actual vs predicted group cell 
   counts. Also included is a listing of the following percentages:
      1. Correctly predicted         2. Model sensitivity
      3. Model specificity           4. False Positive
      5. False Negative

^anova^ provides an ANOVA of discriminant scores vs the group variable.
   Bartlett's test for equal variances in included.

^graph^ provides a classification graph showing correctly and incorrectly 
   classified cases.

^detail^ creates and lists the following for each retained case:
      1. Group    : actual group value                 
      2. PRED     : predicted group value
      3. DIFF     : a star indicating misclassified cases
      4. LnProb1  : logistic probability of grouyp 1 membership
      5. DscIndex : discriminant index
      6. DscScore : discriminant score
  
^keep^ allows the user to keep the variables created in the Detail option.
  The data set in memory is altered, so care must be taken when saving the
  resultant file to disk.
        
Examples
--------
        . ^discrim foreign price mpg length^
        
        . ^discrim foreign price mpg length, p a gr d^

        . ^discrim foreign price mpg length, detail keep^ 

Also see
--------
STB-5 (Jan1992): smv3 - Hilbe, "Regression based dichotomous discriminant 
  analysis".  
Selvin, Steve (1995, 1996) "Practical Biostatistical Methods", Chap 6.
  Explanation and use of the 1st version of the ^discrim^ command. 

Additional help
---------------
Joseph Hilbe, Dept of Sociology, Arizona State University
Email: atjmh@@asuvm.inre.asu.edu