Correct use and analysis of ANOVA?
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MBBinWI.
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- May 27, 2010 at 4:03 pm #53464
RiderParticipant@Ghost-RiderInclude @Ghost-Rider in your post and this person will
be notified via email.I see some of the forum gurus are back on. I am prepared for the assault, but I’ll pose my query anyway:
I have performance rankings for several hundred employees at a particular location. I have a group of current employees and a group of terminated employees and their rankings. I ran an ANOVA and obtained F=0.516 at F-crit=3.9. My null is that there is no difference in the rankings of employees who stay and those who quit voluntarily. With my results I think I should fail to reject the null. I have a VP, however, who is emphatic that he knows for certain that those who quit are always low performers. My results don’t seem to support that assertion. Is ANOVA a proper tool in this case or am I just off the mark again?0May 27, 2010 at 5:13 pm #190220
KluttzMember@Union-of-Conjoined-ScientistsInclude @Union-of-Conjoined-Scientists in your post and this person will
be notified via email.Define “employee rankings”. Is it a 1-5 scale? A straight ranking 1 through n?
0May 27, 2010 at 5:22 pm #190221There are many interesting points
1. What is a VP ?
2. In my exp . only the best people leave first ( In a sinking ship , the rats ( best swimmers) are the first to jump !
3. You are dealing with ordinal data ( ratings ) – do yu think ANOVA is the right tool ? Without ensuring that , you cannot make conclusionsJust my opinion
0May 27, 2010 at 5:31 pm #190222
RiderParticipant@Ghost-RiderInclude @Ghost-Rider in your post and this person will
be notified via email.Employees are ranked from 1 (the top) to n (the bottom).
0May 27, 2010 at 5:33 pm #190223
RiderParticipant@Ghost-RiderInclude @Ghost-Rider in your post and this person will
be notified via email.1. Vice President
2. Even a cursory look at my data does not indicate which rats are hitting the water.
3. My point exactly, which is why I’m asking.0May 27, 2010 at 6:44 pm #190224
KluttzMember@Union-of-Conjoined-ScientistsInclude @Union-of-Conjoined-Scientists in your post and this person will
be notified via email.Mann Whitney
500 dollars please.
0May 27, 2010 at 7:06 pm #190225
RiderParticipant@Ghost-RiderInclude @Ghost-Rider in your post and this person will
be notified via email.Hmm. Ordinal data, independent samples of dissimilar size. I really need a mentor.
Thanks.0May 27, 2010 at 11:45 pm #190228
MBBinWIParticipant@MBBinWIInclude @MBBinWI in your post and this person will
be notified via email.Try binary logistic regression. Your two states are employed, or quit. Your predictor is rank. If you want to include employed, quit, or fired, you could do a nominal logistic regression.
Good to see you on the board, Ghost.
0May 28, 2010 at 2:16 pm #190240
RiderParticipant@Ghost-RiderInclude @Ghost-Rider in your post and this person will
be notified via email.Okay, now we’re getting over my head.
0May 28, 2010 at 3:58 pm #190241What action to you or your boss propose to take on your findings?
0May 28, 2010 at 5:35 pm #190244
RiderParticipant@Ghost-RiderInclude @Ghost-Rider in your post and this person will
be notified via email.We are attempting to see if we can predict the likelihood of someone quitting employment by looking at their performance ranking in the company. I have 1332 data points; some are still employed, others not. I’ve run the regression test mentioned above, but it’s way over my head and analyzing the results is even more over my head.
0May 29, 2010 at 6:10 am #190246why do yu take up tasks which are beyond you ?
0June 1, 2010 at 12:39 pm #190258
RiderParticipant@Ghost-RiderInclude @Ghost-Rider in your post and this person will
be notified via email.Thank you for the question bbusa. Though it really is not relevant to this thread, I’m always up for a bit of banter on the forum. Before I respond, however, I would like to send thanks to MBBinWI, who provided information that has allowed me to find several of the missing pieces to my puzzle. Such relevant, germane, and fitting (proving a point with synonyms here) advice are the hallmark of collaboration, in my opinion.
Now back to your question. I can only infer that you have seen other of my postings in the past as your question denotes a bit of historically present sarcasm in it; fair enough if so, my apologies if not. If you have seen past queries then you already have the answer to your question and I wouldnt insult you by regurgitating that which you must know.
If you have not seen my past posts, then your question is just a bit of banter, or youre just a jerk. Im cool with it either way. I wont even mention that you seem ill-equipped to write standard English-you should learn how to begin a sentence or question as this concept seems beyond you. Moreover, I would suggest reviewing any English grammar book you may have handy and learn the proper spelling of the second person singular; spelling you correctly seems beyond you. The whole which and that thing in American English is probably definitely beyond you so I wont even get into it.
Now that Ive had my turn at banter, the answer to your question is because Ive been told to.
0June 3, 2010 at 3:10 am #190264
MBBinWIParticipant@MBBinWIInclude @MBBinWI in your post and this person will
be notified via email.Ghost: My pleasure. Hope the “task that was beyond you” has been accomplished.
0June 3, 2010 at 6:00 am #190267“I’ve run the regression test mentioned above, but it’s way over my head and analyzing the results is even more over my head.”
Why the hell did you run a reg. if the analysis was way over your head?
BTW : Your English is funny , too . You don’t need to speak Queen’s English to understand regression !
0June 3, 2010 at 8:22 am #190268
Venugopal GParticipant@venu_creativeInclude @venu_creative in your post and this person will
be notified via email.Ghost Rider wrote:
I see some of the forum gurus are back on. I am prepared for the assault, but I’ll pose my query anyway:
I have performance rankings for several hundred employees at a particular location. I have a group of current employees and a group of terminated employees and their rankings. I ran an ANOVA and obtained F=0.516 at F-crit=3.9. My null is that there is no difference in the rankings of employees who stay and those who quit voluntarily. With my results I think I should fail to reject the null. I have a VP, however, who is emphatic that he knows for certain that those who quit are always low performers. My results don’t seem to support that assertion. Is ANOVA a proper tool in this case or am I just off the mark again?Hi,
As per my understanding, Test conditions are as below
1. Compare two groups – Stay Vs Quit
2. Data Type – Ordinal and it is Attribute dataSo ANOVA cannot be used. Since the data is Attribue 2-sample poisson rate test should be used.
But I dont think so that we should consider rankings as continuous.
But there are some people who do consider them as continuous. If so the tools are as below1. If they are indendepent samples, and focus is to compare mean or median and when the data is normal, use 2-sample t test.
2. If they are indendepent samples, and focus is to compare mean or median and when the data is non-normal, use Mann-Whitney test.
3. If they are indendepent samples, and focus is to compare standard deviation or variance , use 2 variances test.
4. If they are dendepent samples, use paired t test.But one basic question my friend. You are talking about predicting the likelihood of someone quitting employment by looking at their performance ranking in the company.
But have you done the MSA on the data collected? How can you prove the data collected is calibrated and we can rely on the same? Because the whole prediction is based on how correct the data is. According to me you will not get a good data i.e., employees giving honest ratings which when analysed says that these employees are planning to leave or stay back. Just a thought.Venu.
0June 3, 2010 at 1:20 pm #190275
RiderParticipant@Ghost-RiderInclude @Ghost-Rider in your post and this person will
be notified via email.If bbusa is trying to achieve something with what appears to be a dressing down of yours truly, I fear he has failed. You see, bbusa, your last question only provides the evidence that I didn’t actually need to show that you have no clue what you are talking about. Knowing something and being able to clearly explain it are two different things. But if it makes you feel better then go ahead. And understanding reg is great, but what if you can’t explain it?
0June 3, 2010 at 5:01 pm #190276Jerk or no Jerk , I simply can’t get over the fact the you tried regression for the situation described & expected others to show you the way !
You owe an explanation to your organization that must have spent a few thousand dollars to get you trained .
BTW : I’d like to be paid to explain regression in a way that you would understand0June 3, 2010 at 6:54 pm #190280
ArguetaMember@[email protected]Include @[email protected] in your post and this person will
be notified via email.I would use chi-squared test.
0June 28, 2010 at 5:18 pm #190380
RiderParticipant@Ghost-RiderInclude @Ghost-Rider in your post and this person will
be notified via email.Hi bbusa,
It’s been quite some time since I’ve posted as I decided to take your advice. Sort of. Before I explain, however, I must digress. I did not expect anyone to show me anything. This forum is meant as a means to guide those of us who are clueless; to a point. My Wisconsin friend indeed guided me, you did not. Also, you make assertions that a true Black Belt would not; my company has spent no money, zero, zilch, nada on getting me trained. That is probably part of the problem. Someone got six sigma in his head and I got picked. I’m attempting to learn this all on my own, with the help of course of some folks I’ve met recently. Also, I would not pay you for anything. It took all of about 20 minutes for someone to explain regression to me. Your services weren’t needed.
You showed your hand in a post when you mentioned the Queen’s English. It’s referred to as the King’s English as a result of the King James Bible. It’s simply a figure of speech that you bastardized in a failed attempt to show your intelligence. We see what that got you.
Anyway, I’m done with my light-hearted banter, pal. I went on a forum here in Houston and decided to see if there were any Six Sigma groups around. There were. Guess what; I went. When the head guy asked if anyone had questions, I piped up. I explained my situation and got the help I needed.
Those who might recognize me on this forum know I’m the first one to proclaim my ignorance. You, conversely, are too stupid to do so.
Later loser, and don’t respond. I’m done waiting for the doc to sand my bunions, and you aren’t important enough to waste otherwise good time.
0June 30, 2010 at 5:58 pm #190385
MBBinWIParticipant@MBBinWIInclude @MBBinWI in your post and this person will
be notified via email.Ghost: Wasn’t worth the time. I just ignore ignorance. Glad to hear you found a local support group. You can always post here and wade through the inane banter. You at least are diligent enough to do as much as you can before asking for help – more than I can say for a number of BB’s (that I’m working with, and that come to this forum).
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