Index: statistics.scm
===================================================================
--- statistics.scm	(revision 26685)
+++ statistics.scm	(working copy)
@@ -564,7 +564,8 @@
       (let loop ((i 0))
         (if (= i (+ 1 k))
           sum-up-to-k
-          (set! sum-up-to-k (+ sum-up-to-k (binomial-probability n i p)))))))
+          (begin (set! sum-up-to-k (+ sum-up-to-k (binomial-probability n i p)))
+                 sum-up-to-k)))))
 
   ;; POISSON-PROBABILITY
   ;; Rosner 100
@@ -1127,7 +1128,7 @@
                             (if (= i number-tied)
                               (reverse result)
                               (loop (+ 1 i)
-                                    (cons (cons (list-ref (+ first i) sorted-list)
+                                    (cons (cons (list-ref sorted-list (+ first i))
                                                 (list avg-rank))
                                           result))))))))
                   distinct-values)
@@ -1148,7 +1149,7 @@
                                  48)
                               0))
                (var-r1 (- (/ (* n (+ 1 n) (+ 1 (* 2 n))) 24) ties-factor))
-               (T-score (/ (- (abs (- r1 expected-r1)) 0.5) (sqrt (var-r1)))))
+               (T-score (/ (- (abs (- r1 expected-r1)) 0.5) (sqrt var-r1))))
           (* (if (eq? tails ':both) 2 1)
              (- 1 (phi T-score)))))))