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Exam Statistics and Results
Table: ceStatsExam
Aggregation of all Item Stats for the Exam.
| Field | Description | ||
|---|---|---|---|
| StatsID | Unique Identifier for this set of Statistics | ||
| QtyQuestions | Count of all Items on the Exam | ||
| QtyCandidates | Count of all Candidates taking the Exam | ||
| QtyCompetencies | Count of distinct Competencies from all Items on the Exam | ||
| QtySections | Count of Sections on the Exam | ||
| ValueMax | Maximum achievable points for Exam, from sum of all Value Max of Items on the Exam | ||
| QtyCorrect | Total of all QtyCorrect for all Items on the Exam | ||
| QtySkipped | Total of all QtySkipped for all Items on the Exam | ||
| QtyIncorrect | Total of all QtyIncorrect for all Items on the Exam | ||
| RawPercent | x = Count of Correct Items on Exam n = Count of Candidates on Exam k = Count of Items on Exam x/(n*k*100)  graphic | ||
| ValueCorrect | Total of all ValueCorrect for all Items on the Exam | ||
| ValueSkipped | Total of all ValueSkipped for all Items on the Exam | ||
| ValueIncorrect | Total of all ValueIncorrect for all Items on the Exam | ||
| ValueTotal | (ValueCorrect + ValueSkipped + ValueIncorrect) | ||
| ValuePercent | ValueTotal/(ValueMax*100) graphic | ||
| Difficulty | x = Count of Correct Items on Exam n = Count of Candidates on Exam k = Count of Items on Exam x/(n*k) graphic | ||
| RawHigh | Highest QtyCorrect achieved by a Candidate on the Exam | ||
| RawLow | Lowest QtyCorrect achieved by a Candidate on the Exam | ||
| RawMean | Mean (average) QtyCorrect achieved by a Candidate on the Exam | ||
| RawVariance | Variance of QtyCorrect for all Candidates on the Exam | ||
| RawStdev | Standard Deviation of QtyCorrect for all Candidates on the Exam | ||
| ValueHigh | Highest ValueTotal achieved by a Candidate on the Exam | ||
| ValueLow | Lowest ValueTotal achieved by a Candidate on the Exam | ||
| ValueMean | Mean (average) ValueTotal achieved by a Candidate on the Exam | ||
| ValueVariance | Variance of ValueTotal for all Candidates on the Exam | ||
| ValueStdev | Standard Deviation of ValueTotal for all Candidates on the Exam | ||
| ValueMedian | Median (middle) ValueTotal for all Candidates on the Exam | ||
| ValueMode | Mode (most frequent) ValueTotal for all Candidates on the Exam | ||
| PercentDistribution | Text field which holds a summary of the score distributions. Not a statistic, but used in reporting | ||
| QtyPassExam | Count of Candidates that passed Exam. See Candidate Statistics (PassExam) link | ||
| SpearmanRank | n = Number of Candidates RankOdd = Candidates Ranking on Odd Items only compared to all other Candidates on Exam RankEven = Candidates Ranking on Odd Items only compared to all other Candidates on Exam 1 - (6*∑▒(RankOdd-RankEven) | 2 )/(n*(n | 2-1)) graphic |
| SpearmanBrown | (2*SpearmanRank)/1) graphic | ||
| KuderRichardson20 | k = Count of Items on Exam Total Test Variance = Variance of Candidate Raw Scores Sum of p*q = sum of all items p (difficulty) * q (1-p) for all items in Exam k/2)*3)/(Total Test Variance) graphic | ||
| KuderRichardson21 | qtyX = Count Items answered correctly on Exam x ̅ = Mean of QtyCorrect for each Candidate on Exam s = StDev of Raw Scores of all Candidates on Exam qtyX/4)* 5))/6) graphic | ||
| StandardError | s = StDev of QtyCorrect for Exam n = Count of Candidates s/√n graphic |
AlphaCoefficient|k = Count of Items on Exam
Total Test Variance = Variance of Candidate Raw Scores
Sum of Item Variance = Sum of all item variances on Exam
k/7)*8)/(Total Test Variance) graphic|
| Skewness | n = Count of Candidates xi = QtyCorrect for each Candidate on Exam x ̅ = Mean of QtyCorrect on Exam s = StDev of QtyCorrect on Exam n/9) ∑▒10)/√(n* (n-1)) Graphic |
| Kurtosis |
(n(n+1) ∑▒(x_i- x ̅ ) ^4)/11)/12)-6)/13) graphic|
| AlternateSystem | Stores Alternate Value used for Calculation (True, Custom, ZScore, TScore,…) see Alternate Scores link |
| AlternateBase | Alternate used in Alternate Calculations see Alternate Scores link |
| AlternateMean | Alternate Mean used in Alternate Calculations see Alternate Scores link |
| AlternateStDev | Alternate Standard Deviation used in Alternate Calculations see Alternate Scores link |
| QuestionLogitSum | Future use |
| QuestionLogitMean | Future use |
| QuestionLogitVariance | Future use |
| QuestionLogitSquaredSum | Future use |
| QuestionSpreadExpansion | Future use |
| CandidateLogitSum | Future use |
| CandidateLogitMean | Future use |
| CandidateLogitVariance | Future use |
| CandidateLogitSquaredSum | Future use |
| CandidateSpreadExpansion | Future use |
1)
1+SpreamanRank
3)
Total Test Variance- ∑▒〖(p*q)〗
4)
qtyX-1
5)
1-x ̅*(qtyX-x ̅
6)
qtyX*s
8)
Total Test Variance- ∑▒〖Item Variance〗
9)
n-1)(n-2
10)
x_i- x ̅)/s) ^3 graphic
Calculate Population Skewness using Sample Skewness
(SkewS*(n-2
graphic Calculate Population Skewness using Sample Skewness
(SkewS*(n-2
11)
n-1)(n-2)(n-3) s^4 ) - (3〖(n-1)〗^2)/(n-2)(n-3) graphic
Calculate Population Kurtosis using Sample Kurtosis
((KurtS*(n-2)*(n-3
graphic Calculate Population Kurtosis using Sample Kurtosis
((KurtS*(n-2)*(n-3
12)
n-1
13)
n+1
