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Timeline for Clarification on ANOVA mechanism

Current License: CC BY-SA 4.0

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Oct 18, 2020 at 18:31 comment added Robert Long No worries, you're welcome. I feel your pain. This happens to me all the time. I use simulation in many of my answers and regularly find a typo that changes small details (and sometimes large details) in what follows :/ LOL to your last sentence :D
Oct 18, 2020 at 18:08 comment added BruceET Typo. Thanks for spotting that. If I correct it, changes would propagate as follows: MS(Gp) = 51,5, MSA = 14.5, F=3.55, P=0.043. May change it all later, but it may cause extra confusion to make changes immediately. // As it stands: an unintended demo of sensitivity of ANOVA to heteroscedasticity.
Oct 18, 2020 at 17:43 comment added Robert Long Great answer (+1), just wondering if x3 = rnorm(10, 22, 4) should have a standard deviation of 3 rather than 4 ?
Oct 18, 2020 at 17:40 comment added BruceET 2 is numerator DF for F-statistic (3 gps - 1 = 2); 27 is denominator DF (3(10 reps - 1)=27). // The simple formulas I illustrated for MSA and MS(Gp) are for a balanced design. Slightly messier if different numbers of replications in 3 groups. // Added stripchart to show exact values of the ten replications in each group.
Oct 18, 2020 at 17:39 history edited BruceET CC BY-SA 4.0
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Oct 18, 2020 at 11:42 vote accept Nemo
Oct 18, 2020 at 11:41 comment added Nemo Fantastic answer! At first glance, one would assume the three groups x1, x2 and x3 came from the same population (given their similar means and variances), but then ANOVA rejected that assumption! Would you mind clarifying what the two numbers (2, 27) mean? Thanks.
Oct 18, 2020 at 8:40 history answered BruceET CC BY-SA 4.0