
Advanced Statistics Advanced Probability and Statistics Math Forum 
 LinkBack  Thread Tools  Display Modes 
November 24th, 2017, 07:05 AM  #1 
Senior Member Joined: Nov 2011 Posts: 230 Thanks: 2  Tukey test
I read the definition in Wikipedia and I don't understand a thing. What is the Tukey test in a few words in Simple English!!! Thank for answering or considering my post. 
November 29th, 2017, 10:41 AM  #2 
Newbie Joined: Oct 2017 From: US Posts: 13 Thanks: 1 
When you compare multiple groups (such as group 1, group 2 and group 3), ANOVA is used. If ANOVA produces p<0.05, you would further like to know which of the following three pairs have 'honestly' significant differences:
If you use ttest, there will be more false positives than expected as 1 ANOVA test now becomes 3 ttests. For example, if alpha=0.05 is set for 1 ANOVA test, alpha will become 10.95*0.95*0.95=0.14 for 3 ttests. This is commonly known as 'alpha inflation' in multiple comparisons. To avoid 'alpha inflation' in multiple comparisons, Tukey's test is used to keep the alpha at the same level and therefore the results are "Honestly Significant Differences (HSD)". This online Tukey's HSD calculator gives explanations for some real data examples. 
November 30th, 2017, 06:27 AM  #3 
Senior Member Joined: Nov 2011 Posts: 230 Thanks: 2 
Why on the alpha level need to be keeped? Thanks on your answer!!! 
December 1st, 2017, 03:39 PM  #4  
Newbie Joined: Oct 2017 From: US Posts: 13 Thanks: 1  Quote:
This famous research study gives you a simple explanation: Why Most Published Research Findings Are False  

Tags 
test, tukey 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
How do I know when to use the Limit Comparison Test over Direct Comp. Test?  leo255  Calculus  2  November 4th, 2014 11:55 AM 
Comparison Test/Limit Comparison Test Questions  fuzzwaz  Calculus  3  November 5th, 2011 02:34 PM 
Test Statistic for Paired Sample Test  semifold  Advanced Statistics  0  January 23rd, 2010 02:17 PM 
z test, t test, or chi squared test  johndeere19  Advanced Statistics  1  July 1st, 2009 11:34 AM 
Find critical value, Ftest value and Test Null Hyp.  symmetry  Advanced Statistics  0  April 7th, 2007 03:05 AM 