QMS 202 Chapter Notes - Chapter Test One: Confidence Interval, Sample Size Determination, Statistical Hypothesis Testing
14 May 2018
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Confidence Interval- Estimate for mean: (sd known for POP. aka Z) –>
You would determine the population mean is between the two values.
Critical Values for Z assume mean: 0 SD: 1 assumption about pop. Area= 1-(lvl of significance)
Critical Values Z- Area= 1-(lvl of significance)
Distribution in order to construct con. Interval estimate- data is normally distributed.
Con. Int. sd unknown – T distribution
Degrees of Freedom:
Confidence Intervals estimate for proportions
Sample size for mean given sd
Sample Size for mean: NOT given SD
If only null= innocent Alternative= guilty
Type one- rejecting Null hyp when it was correct. (convicting innocent man)
Type two- accepting null hypo. when wrong (not convicting guilty man)
Hypothesis testing- Critical value used frequently in solving these questions
If p value = or greater than a – do not reject (to reject # has to be smaller than p)
If answer is this would always be the answer- Do not reject H0. There is insufficient in
evidence to conclude that the true mean point-spread error for all games differs from 0.
Critical Values for T assume mean: 0 SD: 1 assumption about pop. Area= 1-(lvl of significance/2)
Critical Values Z- Area= 1-(lvl of significance)
Distribution in order to construct con. Interval estimate- data is normally distributed.
CALCULATOR:
SAMPLE SIZE
To estimate pop. mean (u)
You will be given the values e and o: you will have to find z using
the following steps
You will also be given % confidence for example 95%
Stat:Dist:norm:Inv
Tail:central
Area:0.95
O(Sd):1
U:0
Z value= 1.96
To estimate Pop. proportion (pie symbol)- % given: Use this (3% = 0.03) →
You will be given values % confidence (you will use to find Z)
If pie isnt given assume it is 0.50
To find z follow steps above
Key to remember:
Df=n-1
%=put in decimal form
Critical values- important
MARGIN OF ERROR
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Confidence interval- estimate for mean: (sd known for pop. aka z) > You would determine the population mean is between the two values. Critical values for z assume mean: 0 sd: 1 assumption about pop. Type one- rejecting null hyp when it was correct. (convicting innocent man) Type two- accepting null hypo. when wrong (not convicting guilty man) Hypothesis testing- critical value used frequently in solving these questions. If p value = or greater than a do not reject (to reject # has to be smaller than p) If answer is this would always be the answer- do not reject h0. There is insufficient in evidence to conclude that the true mean point-spread error for all games differs from 0. Critical values for t assume mean: 0 sd: 1 assumption about pop. You will be given the values e and o: you will have to find z using the following steps.
