Name: _______________________________
In math courses at the national campus Spring 2001 the campuswide population mean grade point average (GPA) m was 1.613. During the Spring 2001 term at the national campus 15 Yapese male students attained a sample mean GPA of 1.133 with a standard deviation sx of 1.407 in math courses. At an alpha a of 0.1, is the Yapese male math GPA statistically significantly lower than the national campus math GPA?
Statistic | Equations | Excel |
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Square root | =SQRT(number) | |
Sample size | n | =COUNT(data) |
Sample mean | =AVERAGE(data) | |
Population mean | m x P(x) n p (binomial) |
=AVERAGE(data) |
Sample standard deviation | sx |
=STDEV(data) |
Population standard deviation | s (binomial) |
=STDEVP(data) |
Slope | =SLOPE(y data, x data) | |
Intercept | =INTERCEPT(y data, x data) | |
Correlation | =CORREL(y data, x data) | |
Binomial probability | = nCr pr q(n-r) | =COMBIN(n,r)*p^r*q^(n-r) |
Calculate a z value from an x | z = | =STANDARDIZE(x, m, s) |
Calculate an x value from a z | x = s z + m | |
Calculate a z value from an value given m and s | =STANDARDIZE(x, m, s/SQRT(n)) | |
Find a probability p from a z value | =NORMSDIST(z) | |
Find a z value from a probability p | =NORMSINV(p) | |
Standard error of the population mean | ||
Standard error of the sample mean | ||
Determining z critical zc from a for confidence intervals or two-tail tests. | =NORMSINV(1-a/2) | |
Error tolerance E of a mean for n ³ 30 using s | =CONFIDENCE(a,s,n) | |
Error tolerance E of a mean for n ³ 30 using sx | E = | =CONFIDENCE(a,sx,n) |
Error tolerance E of a mean for n < 30. Can also be used for n ³ 30. | [no Excel function, determine tc and then multiply by standard error of the mean as shown in the equation] | |
Determining tc from a and the degrees of freedom df for a confidence interval or a two-tail test. | =TINV(a,df) | |
Calculate an value from a tc | =+ m | |
Calculate a confidence interval for a population mean m from a sample mean and an error tolerance E | -E< m <+E | |
Determining zc from a for a two-tail hypothesis test. | =NORMSINV(a/2) [returns only the negative value for zc] |
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Determining zc from a for a one-tail hypothesis test. | =NORMSINV(a) [returns the right tail zc, change the sign for the left tail] |
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Determining tc from a and degrees of freedom df for a two-tail hypothesis test. | =TINV(a, df) [returns only the positive value for tc] |
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Determining tc from a and degrees of freedom df for a one-tail hypothesis test. | =TINV(2a, df) [returns only the left-tail tc, change the sign for right-tail] |
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Determining the one-tail p-value for a z-statistic z for a negative value of z | =NORMSDIST(z) | |
Determining the one-tail p-value for a z-statistic z for a positive value of z | =NORMSDIST(1-z) | |
Determining the two-tail p-value for the absolute value of the z-statistic | =2*NORMSDIST(1-|z|) | |
Determining the one-tail p-value for a t-statistic t and degrees of freedom df | =TDIST(t,df,1) [TDIST accepts only positive values for t, use the absolute value of t] |
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Determining the two-tail p-value for a t-statistic t and degrees of freedom df | =TDIST(t,df,2) |