[gnumeric] Fix Wilcoxon Signed Rank Test handling of ties. [#772718]

[Andreas J. Guelzow <guelzow src gnome org>]

commit 4d22f4f1a8f56abc875be590907c11bb87b76b44
Author: Andreas J. Guelzow <aguelzow pyrshep ca>
Date:   Mon Oct 10 16:25:53 2016 -0600

    Fix Wilcoxon Signed Rank Test handling of ties. [#772718]
    
    2016-10-10  Andreas J. Guelzow <aguelzow pyrshep ca>
    
        * analysis-signed-rank-test.c (analysis_tool_signed_rank_test_two_engine_run):
          ties are based on the predicted mean difference.

 NEWS                                  |    1 +
 src/tools/ChangeLog                   |    5 +++++
 src/tools/analysis-signed-rank-test.c |    4 ++--
 3 files changed, 8 insertions(+), 2 deletions(-)
---
diff --git a/NEWS b/NEWS
index 9d21307..5aebaf0 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,7 @@ Gnumeric 1.12.33
 
 Andreas:
        * Fix export/import of scaling information to/from ODF.
+       * Fix Wilcoxon Signed Rank Test handling of ties. [#772718]
 
 Morten:
        * Speed up sstest part of test suite.
diff --git a/src/tools/ChangeLog b/src/tools/ChangeLog
index 2871e39..00187e0 100644
--- a/src/tools/ChangeLog
+++ b/src/tools/ChangeLog
@@ -1,3 +1,8 @@
+2016-10-10  Andreas J. Guelzow <aguelzow pyrshep ca>
+
+       * analysis-signed-rank-test.c (analysis_tool_signed_rank_test_two_engine_run):
+         ties are based on the predicted mean difference.
+
 2016-10-02  Morten Welinder  <terra gnome org>
 
        * gnm-solver.c (gnm_solver_compute_hessian): New function to
diff --git a/src/tools/analysis-signed-rank-test.c b/src/tools/analysis-signed-rank-test.c
index 1c7d519..9828e9f 100644
--- a/src/tools/analysis-signed-rank-test.c
+++ b/src/tools/analysis-signed-rank-test.c
@@ -5,7 +5,7 @@
  * Author:
  *   Andreas J. Guelzow  <aguelzow pyrshep ca>
  *
- * (C) Copyright 2010 by Andreas J. Guelzow  <aguelzow pyrshep ca>
+ * (C) Copyright 2010, 2016 by Andreas J. Guelzow  <aguelzow pyrshep ca>
  *
  *
  * This program is free software; you can redistribute it and/or modify
@@ -381,7 +381,7 @@ analysis_tool_signed_rank_test_two_engine_run (data_analysis_output_t *dao,
                   (fd_iferror, gnm_expr_new_funcall3
                    (fd_if, gnm_expr_new_binary
                     (gnm_expr_copy (expr_diff),
-                     GNM_EXPR_OP_NOT_EQUAL, make_cellref (0,-2)),
+                     GNM_EXPR_OP_NOT_EQUAL, make_cellref (0,-1)),
                     make_int (1),
                     make_int (0)),
                    make_int (0))));