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1.1       matthew     1: \label{Statistics_Sequence}
                      2: 
                      3: The \textbf{Overall Problem Statistics} page displays the following 
                      4: data about the \textbf{Sequences} selected for evaluation:
                      5: 
                      6: \begin{itemize}
                      7: 
1.2     ! albertel    8: \item \textbf{\#Items}
1.1       matthew     9: 
                     10: The number of assessment items (problem parts) in the sequence.
                     11: 
                     12: \item \textbf{Score} and \textbf{Count} Statistics
                     13: 
                     14: For both the score, the product of the problem weight and the percent awarded,
                     15: and the count, the number of problem parts correct, the following data are 
                     16: computed:
                     17: 
                     18: \begin{itemize}
                     19:     \item \textbf{MEAN}
                     20: 
                     21:     \item \textbf{Standard Deviation}
                     22: 
                     23:     \item \textbf{Maximum}
                     24: 
                     25:     The highest achieved score or count in the data set.
                     26: 
                     27:     \item \textbf{Minimum}
                     28: 
                     29:     The lowest achieved score or count in the data set.
                     30: 
                     31:     \item \textbf{N}
                     32: 
                     33:     The number of students evaluated.
                     34: 
                     35: \end{itemize}
                     36: 
                     37: \item \textbf{KR-21}
                     38: 
                     39: This statistic measures the internal reliability of the data set.
                     40: \textbf{This statistic is relevant for exams only.}  Let $K$ be the
                     41: number of items in your test, $M$ the mean score on the test, $s$ the
                     42: standard deviation of the scores on your test, then the KR-21
                     43: statistic, $rk$, is given by the formula
                     44: 
                     45: $$ rk=\frac{K}{K-1}\cdot \frac{1-(M*(K-M))}{Ks^2} $$
                     46: 
                     47: \end{itemize}