Learn statistics and probability for free—everything you'd want to know about descriptive and inferential statistics. Full curriculum of exercises and videos.Ifyou'reseeingthismessage,itmeanswe'rehavingtroubleloadingexternalresourcesonourwebsite.Ifyou'rebehindawebfilter,pleasemakesurethatthedomains*.kastatic.organd*.kasandbox.orgareunblocked.CoursesSearchDonateLoginSignupSearchforcourses,skills,andvideosMaincontentMathStatisticsandprobabilityMathStatisticsandprobabilityCoursesummaryAnalyzingcategoricaldataAnalyzingonecategoricalvariable:AnalyzingcategoricaldataTwo-waytables:AnalyzingcategoricaldataDistributionsintwo-waytables:AnalyzingcategoricaldataDisplayingandcomparingquantitativedataDisplayingquantitativedatawithgraphs:DisplayingandcomparingquantitativedataDescribingandcomparingdistributions:DisplayingandcomparingquantitativedataMoreondatadisplays:DisplayingandcomparingquantitativedataSummarizingquantitativedataMeasuringcenterinquantitativedata:SummarizingquantitativedataMoreonmeanandmedian:SummarizingquantitativedataInterquartilerange(IQR):SummarizingquantitativedataVarianceandstandarddeviationofapopulation:SummarizingquantitativedataVarianceandstandarddeviationofasample:SummarizingquantitativedataMoreonstandarddeviation:SummarizingquantitativedataBoxandwhiskerplots:SummarizingquantitativedataOthermeasuresofspread:SummarizingquantitativedataModelingdatadistributionsPercentiles:ModelingdatadistributionsZ-scores:ModelingdatadistributionsEffectsoflineartransformations:ModelingdatadistributionsDensitycurves:ModelingdatadistributionsNormaldistributionsandtheempiricalrule:ModelingdatadistributionsNormaldistributioncalculations:ModelingdatadistributionsMoreonnormaldistributions:ModelingdatadistributionsExploringbivariatenumericaldataIntroductiontoscatterplots:ExploringbivariatenumericaldataCorrelationcoefficients:ExploringbivariatenumericaldataIntroductiontotrendlines:ExploringbivariatenumericaldataLeast-squaresregressionequations:ExploringbivariatenumericaldataAssess