62EstimatingaPopulationMeanwithaSmallSample&FindingSampleSizeDay2
Forn30 and isunknown,
(degreesoffreedom=n1)
ConfidenceIntervals:
EX 2
EX 3
Constructthe90%confidenceintervalforthemeanageofRHSseniorsfathersontheir
birthusingthefollowing10randomlyselecteda
sample
claim
Find the p-value for each scenario. Use =0.05 to determine if
we reject or fail to reject H0.
1.
TestStatistic:
t=1.2
(2tailtest)n=25
Pvalue:
reject or fail to reject H0
2.
TestStatistic:
t=2.56
(righttailtest)n=18
Pvalue:
reject or fail to r
Components of Hypothesis Testing
EX 1 After analyzing 106 body temperatures of healthy adults, a medical researcher
makes a claim that the mean body temperature is less than 98.6F.
Expressthisclaiminsymbolicform.
IdentifyH0.
98.6
IdentifyH1.
<98.6
<98.
EX1
a.
Asampleof_RHSseniorsarerandomlyselected
andwhensurveyed_ofthemhavebeenastudent
inRockfordPublicSchoolsforall13years.
FindthebestestimateofthetrueproportionofallRHSseniors
whohavebeenastudentinRPSforall13years.
b. Finda99%confidenceintervalforthetru
Section 73: Testing a Claim about a Mean: Large Samples
sample
ors
claim
Randomsampleof106healthyadultswherex=98.2Fands=0.62F
=98.6
98.6
=98.6
2TT
= 2 x (0.0001)
=0.0002
6.64
6.
7.
Reject H0
since p-value (0.0002) <(0.05)
There is sufficient evidence t