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version 1.5, 2005/01/10 18:01:30 version 1.6, 2005/03/28 21:32:11
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 The \textbf{Overall Problem Statistics} page displays the following   The \textbf{Overall Problem Statistics} page displays the following 
 data about the problems currently in the course:  data about the problems currently in the course:
   
 \begin{itemize}  \begin{description}
   
 \item \textbf{\#Stdnts}  \item{\textbf{\#Stdnts}} Total number of students attempting the problem.
   
 Total number of students attempting the problem.  \item{\textbf{Tries}} Total number of attempts to solve the problem.
   
 \item \textbf{Tries}  \item{\textbf{Max Tries}} Largest number of attempts to solve the problem by a student.
   
 Total number of attempts to solve the problem.  \item{\textbf{Mean Tries}} Average number of attempts.
   
 \item \textbf{Max Tries}  \item{\textbf{S.D. tries}} Standard Deviation of the tries.
   
 Largest number of attempts to solve the problem by a student.  \item{\textbf{Skew Tries}} Skewness of the students tries.
   
 \item \textbf{Mean Tries}  
   
 Average number of attempts.  
   
 \item \textbf{S.D. tries}  
   
 Standard Deviation of the tries.  
   
 \item \textbf{Skew Tries}  
   
 Skewness of the students tries.  
 \[\frac{\sqrt{ \sum{(Xi - Mean)^3} / \#Stdnts}}{\sigma^3}\]  \[\frac{\sqrt{ \sum{(Xi - Mean)^3} / \#Stdnts}}{\sigma^3}\]
   
 \item \textbf{\#YES}  \item{\textbf{\#YES}} Number of students who solved the problem correctly.
   
 Number of students who solved the problem correctly.  \item{\textbf{\#yes}} Number of students who solved the problem by override.
   
 \item \textbf{\#yes}  \item{\textbf{\%Wrng}} Percentage of students who tried to solve the problem but were unable to.
   
 Number of students who solved the problem by override.  \item{\textbf{DoDiff}} Degree of Difficulty of the problem.  
   
 \item \textbf{\%Wrng}  This statistics gives a measure of how many attempts it took the
   students to get the problem correct.  Those students who did not get
   the problem correct are not counted.  A value close to 0 indicates
   most students who got the problem correct did so on the first attempt.
   A value close to 1 indicates many attempts were required for students
   to get the problem correct.  A negative value indicates students were
   given points without attempting the problem.  A value of 'nan' means
   there were no attempts made on the problem.
   
 Percentage of students who tried to solve the problem but were unable to.  
   
 \item \textbf{DoDiff}  
   
 Degree of Difficulty of the problem.    
 \[ 1 - \frac{\#YES+\#yes}{Tries} \]  \[ 1 - \frac{\#YES+\#yes}{Tries} \]
   
 \item \textbf{DoDisc}  \item{\textbf{DoDisc}} Degree of Discrimination of the problem.
   
 Degree of Discrimination of the problem.  
   
 The students are grouped based on their scores on the sequence which   The students are grouped based on their scores on the sequence which 
 contains the homework problem.  The percent score of the bottom 25\% of  contains the homework problem.  The percent score of the bottom 25\% of
Line 60  poor students answered it correctly.  Co Line 48  poor students answered it correctly.  Co
 all of the good students got the problem wrong and the bad students did  all of the good students got the problem wrong and the bad students did
 well.  well.
   
 \end{itemize}  \item{\textbf{weight}} The weight of the problem in the course (``points'').
   The value shown is the weight of the problem for the individual computing the
   statistics.  Individual student or section variations are not shown.
   
   \end{description}
   
   \textbf{Sequence Statistics}, that is compiled statistics on problems based on
   their containing sequence, are also shown.  The following data are shown:
   
   \begin{description}
   
   \item{\textbf{#Items}} The number of problem parts in the sequence.
   
   \item{\textbf{Score Mean}, \textbf{Score STD}, \textbf{Score Max} \textbf{Score Min}}
   The mean, standard deviation, maximum, and minimum of the scores of
   the selected students on the given sequence.
   
   \item{\textbf{Score N}}  The number of the selected students who submitted answers to problem parts in the sequence.
   
   \item \textbf{Count Mean}, \textbf{Count STD}, \textbf{Count Max}, \textbf{Count Min} 
   The mean, standard deviation, maximum, and minum count of correct
   problem parts of the selected students on the given sequence.
   
   \item \textbf{Count N} The number of the selected students who submitted answers to problem parts in the sequence.
   
   \item \textbf{KR-21} The KR-21 reliability statistic measures the internal reliability of a test or exam.
   
   To compute the KR-21 reliability statistic the following formula is used:
   
   \[KR-21 = \frac{K}{K-1} \cdot \frac{1-(M \cdot (K-M))}{K \cdot s^{2}}\]
   
   Where 
   \begin{description}
   \item{$K$} is the number of items in your test
   \item{$M$} the mean score on the test
   \item{$s$} the standard deviation of the scores on your test
   \end{description}
   
   \end{description}
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  Added in v.1.6

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