--- loncom/html/adm/help/tex/Statistics_Overall_Key.tex 2006/08/08 17:47:27 1.8
+++ loncom/html/adm/help/tex/Statistics_Overall_Key.tex 2014/05/27 18:06:24 1.11
@@ -1,4 +1,4 @@
-\label{Statistics_Key}
+\label{Statistics_Overall_Key}
The \textbf{Overall Problem Statistics} page displays the following
data about the problems currently in the course:
@@ -41,7 +41,7 @@ there were no attempts made on the probl
The students are grouped based on their scores on the sequence which
contains the homework problem. The percent score of the bottom 25\% of
-the students is subtracted from the percent score the to top 25\% of
+the students is subtracted from the percent score of the top 25\% of
the students. This yields a number from -1 to 1. 1.0 indicates
all of the good students answered the problem correctly and none of the
poor students answered it correctly. Conversely, a score of -1.0 indicates
@@ -77,7 +77,7 @@ problem parts of the selected students o
To compute the KR-21 reliability statistic the following formula is used:
-\[KR-21 = \frac{K}{K-1} \cdot \frac{1-(M \cdot (K-M))}{K \cdot s^{2}}\]
+\[KR-21 = \frac{K}{K-1} \cdot \left(1- \frac{M \cdot (K-M)}{K \cdot s^{2}} \right)\]
Where
\begin{description}