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Tue Apr 30 01:56:22
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exam 3
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hee's the first page of exam 3:
PSY 418 - Exam 3
10 questions, total points: 76
***Show your work, put final answers in decimal form, stay calm, good luck***
Some useful facts:
For the normal distribution,
95% of observations fall within 1.96 z’s of the mean.
99% of observations fall within 2.58 z’s of the mean.
For t,
With two degrees of freedom, 95% of observation fall within 4.3 t’s of the mean.
With two degrees of freedom, 99% of observation fall within 9.9 t’s of the mean.
With four degrees of freedom, 95% of observation fall within 2.8 t’s of the mean.
With five degrees of freedom, 95% of observation fall within 2.6 t’s of the mean.
With eight degrees of freedom, 95% of observation fall within 2.3 t’s of the mean.
For F,
With two degrees of freedom between groups and six degrees within groups, 95% of observations are less than 5.14.
With six degrees of freedom between groups and two degrees within groups, 95% of observations are less than 19.33.
For Chi-Square,
With one degree of freedom, 95% percent of observations fall below 3.84.
With two degrees of freedom, 95% percent of observations fall below 5.99.
With three degrees of freedom, 95% percent of observations fall below 7.81.
With four degrees of freedom, 95% percent of observations fall below 9.49.
Some useful facts:
sp2=[(n1-1)s12 + (n2-1)s22]/(n1+n2-2)
t(n1+n2-2)=(x1 bar - x2 bar)/[sp(1/n1 + 1/n2)1/2]
b=r*(sy/sx), a=y bar-b*x bar
SSbetween=sum of all groups ni(xbari-xbar)2
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