PROBABILITY AND STATISTICS, WGU C955
QUESTIONS WITH CORRECT ANSWERS 2025
Boxplotf-fCORRECTfANSWERanfimagefthatfhasfmin,fQ1,fmedian,fQ3,fmax
Histogramf-fCORRECTfANSWERAfgraphicalfrepresentationf--
fbars,fmeasuringf theffrequencyf withinf eachf interval
Skewedfrightf-
f CORRECTfANSWERNotf afsymmetricfdistribution,fthef tailf isf onf thef right,f i.e.fextraf stufffonf th
efright
Measuresfoffcenterf-fCORRECTfANSWERMedian,fthefmeanf(andfmode)
Measuresfoffspreadf-fCORRECTfANSWERRange,fIQRf&fstandardfdeviation
StandardfDeviationfRulef-
f CORRECTfANSWER68%f offthefdataf aref withinf1f standardfdeviation,f95%f aref withinf2,f99.7f
arefwithinf3fstandardfdeviationsffromfthefmean.
Forfskewedfdata,fusefthesefforfcenterfandfspreadf-
f CORRECTfANSWERInf thisfsituation,f wefusefmedianf (forf center)f &fIQRf (forfspread)
Explanatoryfvariablef-fCORRECTfANSWERInfafstudy,fwhatfwefthinkfisfthef"cause"
Responsefvariablef-fCORRECTfANSWERInfafstudy,fwhatfwefthinkfisfthef"effect"
Scatterfplotf-fCORRECTfANSWERAfgraphicalfrepresentationfoffQf->fQ
Twofwayftablef-fCORRECTfANSWERAfgraphicalfrepresentationfoffCf->fC
Side-byfsidefboxf-fCORRECTfANSWERAfgraphicalfrepresentationfoffCf->fQ
Linearfrelationshipf-fCORRECTfANSWER"shapedflikefafline"
Correlationfcoefficient,frf-fCORRECTfANSWERBetweenf-
1fandf1;fmeasuresfhowfclosefthefpointsfareftoftheflinefandfifftheftrendfisfuphillf(positive)forfdow
nhillf(negative).
rf=f-0.2,fforfexamplef-
f CORRECTfANSWERThisf isf anf examplefoffaf correlationf coefficientf thatfrepresentsf af weakfn
egativefcorrelation.
rf=f0.9,fforfexamplef-
f CORRECTfANSWERThisf isf anf examplefoffaf correlationf coefficientf thatfrepresentsf afstrongf
positivefcorrelation.
Linearfregressionflinef-
f CORRECTfANSWERAf linef thatffitsfthefdatafasf closef asfpossible,fusedf tof makefpredictions
Interpolationf-
f CORRECTfANSWERMakingf predictionsf*within*f thef rangef off yourf data.fThisf isf usuallyf acc
urate.
Extrapolationf-
f CORRECTfANSWERMakingf predictionsf*outside*f offthef rangef off yourf data.fThisf isf generall
yfafbadfidea.
Simpson'sfParadoxf-
f CORRECTfANSWERWhenfsplitf up,feachfdataf setfcanf havef afpatternfwhichf goesfawayf whe
nfallfthefdatafisfcombined.
Onlyfwayftofprovefcausationf-
f CORRECTfANSWERExperiments,fbecauseftheyf accountfforf lurkingf variables
QUESTIONS WITH CORRECT ANSWERS 2025
Boxplotf-fCORRECTfANSWERanfimagefthatfhasfmin,fQ1,fmedian,fQ3,fmax
Histogramf-fCORRECTfANSWERAfgraphicalfrepresentationf--
fbars,fmeasuringf theffrequencyf withinf eachf interval
Skewedfrightf-
f CORRECTfANSWERNotf afsymmetricfdistribution,fthef tailf isf onf thef right,f i.e.fextraf stufffonf th
efright
Measuresfoffcenterf-fCORRECTfANSWERMedian,fthefmeanf(andfmode)
Measuresfoffspreadf-fCORRECTfANSWERRange,fIQRf&fstandardfdeviation
StandardfDeviationfRulef-
f CORRECTfANSWER68%f offthefdataf aref withinf1f standardfdeviation,f95%f aref withinf2,f99.7f
arefwithinf3fstandardfdeviationsffromfthefmean.
Forfskewedfdata,fusefthesefforfcenterfandfspreadf-
f CORRECTfANSWERInf thisfsituation,f wefusefmedianf (forf center)f &fIQRf (forfspread)
Explanatoryfvariablef-fCORRECTfANSWERInfafstudy,fwhatfwefthinkfisfthef"cause"
Responsefvariablef-fCORRECTfANSWERInfafstudy,fwhatfwefthinkfisfthef"effect"
Scatterfplotf-fCORRECTfANSWERAfgraphicalfrepresentationfoffQf->fQ
Twofwayftablef-fCORRECTfANSWERAfgraphicalfrepresentationfoffCf->fC
Side-byfsidefboxf-fCORRECTfANSWERAfgraphicalfrepresentationfoffCf->fQ
Linearfrelationshipf-fCORRECTfANSWER"shapedflikefafline"
Correlationfcoefficient,frf-fCORRECTfANSWERBetweenf-
1fandf1;fmeasuresfhowfclosefthefpointsfareftoftheflinefandfifftheftrendfisfuphillf(positive)forfdow
nhillf(negative).
rf=f-0.2,fforfexamplef-
f CORRECTfANSWERThisf isf anf examplefoffaf correlationf coefficientf thatfrepresentsf af weakfn
egativefcorrelation.
rf=f0.9,fforfexamplef-
f CORRECTfANSWERThisf isf anf examplefoffaf correlationf coefficientf thatfrepresentsf afstrongf
positivefcorrelation.
Linearfregressionflinef-
f CORRECTfANSWERAf linef thatffitsfthefdatafasf closef asfpossible,fusedf tof makefpredictions
Interpolationf-
f CORRECTfANSWERMakingf predictionsf*within*f thef rangef off yourf data.fThisf isf usuallyf acc
urate.
Extrapolationf-
f CORRECTfANSWERMakingf predictionsf*outside*f offthef rangef off yourf data.fThisf isf generall
yfafbadfidea.
Simpson'sfParadoxf-
f CORRECTfANSWERWhenfsplitf up,feachfdataf setfcanf havef afpatternfwhichf goesfawayf whe
nfallfthefdatafisfcombined.
Onlyfwayftofprovefcausationf-
f CORRECTfANSWERExperiments,fbecauseftheyf accountfforf lurkingf variables
