# Test pstrong pstrong0 2 not equal so probability

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Test P(Strong) = P(Strong|0-2), not equal, so dep6.1-6.2 Probability Distributionsdiscrete probab dist: set of distinct, separable outcomescontinuous probab dist: w/in a range of cont outcomes (PDF)Empirical Probab dist: observe frequencies and use proportion of times an outcome occurs in the sampleTheoretical probab dist: for various outcomes based on assumptions about random phenomNormal Distribution: increasing/decreasing meanmoves the curve along the horizontal axis, the SDdetermines spread of curve68.2% of data falls w/in 1 SD around mean95.4% = 2 SD, 99.7% = 3 SDz-score: score indicating the direction and degreethat any raw score deviates from mean in SD unitsN(mean, SD), z = x – mean/SD, x = mean + (z*SD)Ex: N(60, 20).Find percentage of more than 55 minZ=(55-60/20 = -0.25, corresponding: 0.4013, 1-0.4013 = 0.5987 = 59.87%Probability of selecting btwn 10 and 30 minZ=10-60/20 = -2.5, 0.0062, Z=30-60/20=-1.5, 0.0668, 0.0668-0.0062 = 0.0606Percentile rank of 100 minZ=100-60/20=40/20=2, corresponds to 0.9772, 98thpercentileTwo numbers that define middle 95% dist100-95=5/2=2.25, z-score at 0.025 = -1.96, 1.96x1 = 60+(1.96)(20) = 99.2x2 = 60+(-1.96)(20) = 20.8Measureof CTLevel of MAmountof info about datasetAffectedby outliersModeNominalleastleastMedian0.5(n+1)Ordinal,interval,ratioMediumMediumMeanInterval,ratiomostmost# thefsfF(x)cf%C%x-xbar(x-xbar)^2F(x-xbar)^2133311.1111.11-3.2610.6331.8927141025.9337.04-2.265.1135.77326127.4144.44-1.261.593.18510502237.0481.480.740.555.563182511.1192.591.743.039.0912224277.411007.7459.91119.82total27115100205.25VariationratiorangeVarianceSDNominalxXxOrdinalXxIntervalxratiox
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