chapter 8 student data files.xlsx - we know pop std dev we don't know pop std deviation sample mean z\u03b1\/2 excel function to calculate zscore =norm.s.inv

# chapter 8 student data files.xlsx - we know pop std dev we...

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we know pop std dev we don't know pop std deviation sample mean excel function to calculate zscore =norm.s.inv standard normal distribution norm.s.inv at alpha over 2 z α/2
common confidence levels: level of significance 90% 10% 0.05 1.644854 95% 5% 0.025 1.959964 99% 1% 0.005 2.575829 level of significance is called the alpha value outside of range does not contain the true population or mean is equal to 1 minus the confidence level margin of error tells us how wide our interval needs to be in order to reach the designated level of confidence 8.2 Confidence Level when σ is known Formula for the Confidence Interval for the mean (σ known) std error of mean - from chp 7 margin of error known as α - alpha [email protected] x α/ x x α/ x σ z x LCL σ z x UCL 2 2 n σ σ x x α/ x σ z ME 2
pha/2
x α/ x x α/ x σ z x LCL σ z x UCL 2 2
n-sample size 35 xbar -sample mean 247.8 std deviation 39 confidence 0.9 level of sign-alpha 0.1 alpha /2 0.05 critical zscore @ alpha/2 1.644854 std error 6.592203 margin of error 10.84321 upper confidence 258.6432 lower confidence 236.9568 we are 90% confident mean luxury hotel cost per night will cost between \$236.96 and \$258.64.
a b c n 30 60 xbar 507 std 63 confidence 0.9 alpha 0.1 alpha/2 0.05 zscore 1.64485362695147 std error 11.50217 8.133265 moe 18.91939 13.37803 upper lower
n-sample size 34 xbar- sample mean 21.2 pop std deviation 3.9 confidence 0.98 alpha 0.02 alpha/2 0.01 critical z-score 2.326348 std error 0.668844 margin of error 1.555965 upper 22.75596 lower 19.64404 we are 98% confident that average fuel economy for passenger vehicles in the Usis between 19.64 and 22.76 Yes, this does validate the EPA claims
mpg.
n 48 65 19 xbar 39 63 81551 std 9 11 4517 confidence 0.95 0.98 0.9 alpha 0.05 0.02 0.1 alpha/2 0.025 0.01 0.05 zscore 1.959964 2.326348 1.64485362695147 std error 1.299038 1.364382 1036.27086989333 moe 2.546068 3.174027 1704.5138988482 lower 36.45393 59.82597 79846.4861 upper 41.54607 66.17403 83255.5139
n 40 xbar 187 n-sample s 35 std 50 xbar -samp 247.8 std deviati 39 confidence 0.95 confidence 0.9 level of sig 0.1 alpha 0.05 alpha /2 0.05 alpha/2 0.025 critical zs 1.644854 zscore 1.959964 std error 6.592203 std error 7.905694 moe 15.49488 margin of e10.84321