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Exam Statistics and Results

Table: ceStatsExam

Aggregation of all Item Stats for the Exam.

FieldDescription
StatsIDUnique Identifier for this set of Statistics
QtyQuestionsCount of all Items on the Exam
QtyCandidatesCount of all Candidates taking the Exam
QtyCompetenciesCount of distinct Competencies from all Items on the Exam
QtySectionsCount of Sections on the Exam
ValueMaxMaximum achievable points for Exam, from sum of all Value Max of Items on the Exam
QtyCorrectTotal of all QtyCorrect for all Items on the Exam
QtySkippedTotal of all QtySkipped for all Items on the Exam
QtyIncorrectTotal of all QtyIncorrect for all Items on the Exam
RawPercentx = Count of Correct Items on Exam
n = Count of Candidates on Exam
k = Count of Items on Exam

x/(n*k*100) FIXME graphic
ValueCorrectTotal of all ValueCorrect for all Items on the Exam
ValueSkippedTotal of all ValueSkipped for all Items on the Exam
ValueIncorrectTotal of all ValueIncorrect for all Items on the Exam
ValueTotal(ValueCorrect + ValueSkipped + ValueIncorrect)
ValuePercentValueTotal/(ValueMax*100) FIXME graphic
Difficultyx = Count of Correct Items on Exam
n = Count of Candidates on Exam
k = Count of Items on Exam

x/(n*k) FIXME graphic
RawHighHighest QtyCorrect achieved by a Candidate on the Exam
RawLowLowest QtyCorrect achieved by a Candidate on the Exam
RawMeanMean (average) QtyCorrect achieved by a Candidate on the Exam
RawVarianceVariance of QtyCorrect for all Candidates on the Exam
RawStdevStandard Deviation of QtyCorrect for all Candidates on the Exam
ValueHighHighest ValueTotal achieved by a Candidate 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) SpearmanBrown (2*SpearmanRank)/1) 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) 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) StandardError s = StDev of QtyCorrect for Exam n = Count of Candidates s/√n 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) 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)) 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))

Kurtosis n = Count of Candidates xi = QtyCorrect for each Candidate on Exam x ̅ = Mean of QtyCorrect for Exam s = StDev of QtyCorrect for Exam

Calculate Sample Kurtosis KurtS (n(n+1) ∑▒(x_i- x ̅ ) ^4)/11)/12)-6)/13)

AlternateSystem Stores Alternate Value used for Calculation (True, Custom, ZScore, TScore,…) see Alternate Scores

AlternateBase Alternate Base used in Alternate Calculations see Alternate Scores

AlternateMean Alternate Mean used in Alternate Calculations see Alternate Scores

AlternateStDev Alternate Standard Deviation used in Alternate Calculations see Alternate Scores

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
2) , 7)
k-1
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 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) Calculate Population Kurtosis using Sample Kurtosis ((KurtS*(n-2)*(n-3
12)
n-1
13)
n+1