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Item Statistics and Results
Table: ceStatsExamSection
Aggregate of Item Stats, grouped by Section. Also derives some values by aggregating from Candidate performance by Section from Registration Section Stats.
| Field | Description |
|---|---|
| StatsID | Unique Identifier for this set of Statistics |
| SectionID | ID of Section all Items are a member of |
| QtyQuestions | Count of all Items in this Section |
| QtyCorrect | Total of all QtyCorrect for all Items in this Section |
| QtySkipped | Total of all QtySkipped for all Items in this Section |
| QtyIncorrect | Total of all QtyIncorrect for all Items in this Section |
| RawPercent | x = Count of Correct Items in Section n = Count of Candidates on Exam k = Count of Items in Section  |
| ValueCorrect | Total of all ValueCorrect for all Items in this Section |
| ValueSkipped | Total of all ValueSkipped for all Items in this Section |
| ValueIncorrect | Total of all ValueIncorrect for all Items in this Section |
| ValueTotal | (ValueCorrect + ValueSkipped + ValueIncorrect) |
| ValuePercent |  |
| Difficulty | x = Count of Correct Items in Section n = Count of Candidates on Exam k = Count of Items in Section  |
| RawHigh | Highest QtyCorrect achieved by a Candidate for this Section |
| RawLow | Lowest QtyCorrect achieved by a Candidate for this Section |
| RawMean | Mean (average) QtyCorrect achieved by a Candidate for this Section |
| RawVariance | Variance of QtyCorrect for all Candidates for this Section |
| RawStdev | Standard Deviation of QtyCorrect for all Candidates for this Section |
| ValueMax | Maximum achievable points for Group from sum off all Value Max of Items in Section |
| ValueHigh | Highest ValueTotal achieved by a Candidate for this Section |
| ValueLow | Lowest ValueTotal achieved by a Candidate for this Section |
| ValueMean | Mean (average) ValueTotal achieved by a Candidate for this Section |
| ValueStdev | Standard Deviation of ValueTotal for all Candidates for this Section |
| ValueVariance | Variance of ValueTotal for all Candidates for this Section |
| ValueMedian | Median (middle) ValueTotal for all Candidates for this Section |
| ValueMode | Mode (most frequent) ValueTotal for all Candidates for this Section |
KuderRichardson20 k = Count of Items in Section Total Section Variance = Variance of Candidate Raw Scores for Section Sum of p*q = sum of all items p (difficulty) * q (1-p) for all items in Section
k/1)*2)/(Total Section Variance)
StandardError s = StDev of QtyCorrect for Exam n = Count of Candidates s/√n
Skewness n = Count of Candidates xi = QtyCorrect for each Candidate on Section x ̅ = Mean of QtyCorrect for Section s = StDev of QtyCorrect for Section
Calculate Sample Skewness SkewS n/3) ∑▒4)/√(n* (n-1))
Kurtosis n = Count of Candidates xi = QtyCorrect for each Candidate on Section x ̅ = Mean of QtyCorrect for Section s = StDev of QtyCorrect for Section
Calculate Sample Kurtosis KurtS (n(n+1) ∑▒(x_i- x ̅ ) ^4)/5)/6)-6)/7)
