Summary One-factor ANOVA steps

Steps in one-factor ANOVA:
1. State the null and alternative hypothesis:
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2.
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Compute the test statistic:
Roundsto 3decimal
places


To do this, several sub-steps need to be followed first:
1..Load & look at the data: Sst cn ixs
ofrows 1 variance
sample




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RoundsSSBto 3decimalplaces

Notice that this dataset is in a “wide” format. Sometimes we want to store data in
a “long” (“narrow”) format. We can use the reshape2 package to do this:




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RoundsSSWto 3decimalplaces

, Notice that the factor names are shortened, so we need to change this:




2. Compute sample statistics to describe the data:
Sample sizes & total sample size:




Group means & grand mean:



Totalvariance Is o freedom
degrees
meansquaretotal