1/1POINTS
Afitnesscenterclaimsthathemeanamountoftimethatapersonspendsathegym pervisitis33 minutes.Identifythenulhypothesis,H0,andthealternative hypothesis,Ha,intermsoftheparameterμ.
H0:μ≠33;Ha:μ=33 H0:μ=33;Ha:μ
...
1/1POINTS
Afitnesscenterclaimsthathemeanamountoftimethatapersonspendsathegym pervisitis33 minutes.Identifythenulhypothesis,H0,andthealternative hypothesis,Ha,intermsoftheparameterμ.
H0:μ≠33;Ha:μ=33 H0:μ=33;Ha:μ≠33 H0:μ≥33;Ha:μ<33
H0:μ≤33;Ha:μ>33
AnswerExplanation
Corectanswer:
H0:μ=33;Ha:μ≠33
Letheparameterμ beusedtorepresenthemean.Thenulhypothesisisalways statedwithsomeform ofequality:equal(=),greaterthanorequalto(≥),orlessthan orequalto(≤).Therefore,inthiscase,thenulhypothesisH0 isμ=33.The alternativehypothesisiscontradictorytothenulhypothesis,soHa isμ≠33.
QUESTION2 1/1POINTS
Theanswerchoicesbelowrepresentdifferenthypothesistests.Whichofthechoices areright-tailedtests?Selectalcorrectanswers.
•
H0:X≥17.1,Ha:X<17.1
•
•
H0:X=14.4,Ha:X≠14.4
•
•
H0:X≤3.8,Ha:X>3.8
•
•
H0:X≤7.4,Ha:X>7.4
•
•
H0:X=3.3,Ha:X≠3.3
•
AnswerExplanation
Corectanswer:
Remembertheformsofthehypothesistests.
• Right-tailed:H0:X≤X0,Ha:X>X0.
• Left-tailed:H0:X≥X0,Ha:X7.4
• H0:X≤3.8,Ha:X>3.8
QUESTION3 0/1POINTS
FindtheType Ierrorgiventhathenulhypothesis,H0,is:abuildinginspectorclaims thatnomorethan15% ofstructuresinthecountywerebuiltwithoutpermits.
Thebuildinginspectorthinksthatnomorethan15% ofthestructuresinthecounty werebuiltwithoutpermitswhen,infact,nomorethan15% ofthestructuresrealywere builtwithoutpermits.
Thebuildinginspectorthinksthatmorethan15% ofthestructuresinthecountywere builtwithoutpermitswhen,infact,morethan15% ofthestructuresrealywerebuilt withoutpermits.
Thebuildinginspectorthinksthatmorethan15% ofthestructuresinthecountywere builtwithoutpermitswhen,infact,atmost15% ofthestructureswerebuiltwithout permits.
Thebuildinginspectorthinksthatnomorethan15% ofthestructuresinthecounty werebuiltwithoutpermitswhen,infact,morethan15% ofthestructureswerebuilt withoutpermits.
AnswerExplanation
Corectanswer:
AType Ierroristhedecisionnotorejecthenulhypothesiswhen,infact,itisfalse.In thiscase,theType Ierroriswhenthebuildinginspectorthinksthatnomore
than15% ofthestructureswerebuiltwithoutpermitswhen,infact,more than15% ofthestructureswerebuiltwithoutpermits.
Youranswer:
Content attribution- Opens a dialog
QUESTION4 1/1POINTS
Sup oseachefclaimsthathermeatbalweightislessthan4 ounces,onaverage. Severalofhercustomersdonotbelieveher,sothechefdecidestodoahypothesistest, ata10% significancelevel,topersuadethem.Sheco ks14 meatbals.Themean weightofthesamplemeatbalsis3.7 ounces.Thechefknowsfrom experiencethathe standarddeviationforhermeatbalweightis0.5 ounces.
• H0:μ≥4;Ha:μ<4
• α=0.1 (significancelevel)
Whatistheteststatistic(z-score)ofthisone-meanhypothesistest,roundedtotwo decimalplaces?
AnswerExplanation
Corectanswers:
Thehypotheseswerechosen,andthesignificancelevelwasdecidedon,sothenext stepinhypothesistestingistocomputetheteststatistic.Inthisscenario,thesample meanweight,x¯=3.7.Thesamplethechefusesis14 meatbals,son=14.She
knowsthestandarddeviationofthemeatbals,σ=0.5.Lastly,thechefiscomparing
thepopulationmeanweighto4 ounces.So,thisvalue(foundinthenulandalternative
hypotheses)isμ0.Nowwewilsubstitutethevaluesintotheformulatocomputethe teststatistic:
z0=x¯−μ0σn√=3.7−40.514√≈−0.30.134≈−2.24
So,theteststatisticforthishypothesistestisz0=−2.24.
QUESTION5 1/1POINTS
Whatisthep-valueofaright-tailedone-meanhypothesistest,withateststatistic ofz0=1.74?(Donotroundyouranswer;computeyouranswerusingavaluefrom the tablebelow.) z1.51.61.71.81.90.000.9330.9450.9550.9640.9710.010.9340. 9460.9560.9650.9720.020.9360.9470.9570.9660.9730.030.9
370.9480.9580.9660.9730.040.9380.9490.9590.9670.9740.0
50.9390.9510.9600.9680.9740.060.9410.9520.9610.9690.97
50.070.9420.9530.9620.9690.9760.080.9430.9540.9620.970
.9760.090.9440.9540.9630.9710.977
AnswerExplanation
Corectanswers:
Thep-valueistheprobabilityofanobservedvalueofz=1.74 orgreaterifthenul hypothesisistrue,becausethishypothesistestisright-tailed.Thisprobabilityisequalto theareaundertheStandardNormalcurvetotherightofz=1.74.
..................................................................................CONTINUED............................................................................................
[Show More]
.png)
 2e Peter Olver, Chehrzad Shakiban.png)
