9. Analysis of Variance (ANOVA) - Dr. A.G. Picciano

[rusbc]

Helped me for my project! Not exciting stuff but it is very informative.

[apicciano]

@rusbc

Good luck with your studies!

Dr. P.

[Smorphine]

One little question: what is the difference in SPSS between the commands Analyze>Compare Means>One-Way ANOVA and Analyze>General Linear Model>Univariate? Are both ANOVAS?

[mysoukouss]

Thank you Picciano. I got B's in y grad stat classes. I studied hard /cramed :) to pass the class exam. i really need to go through the material slowly and your review is excellent.

Thank you for downloading the PPoints. They are vv helpful.

[shilpaphansalkar]

hello, I have a confusion if the value is less than 0.05 that it is said to be statistically significant. I didn't understand the concept related to 95%. Can u please explain?

[tfbl928]

I'm not going to my class anymore, I'm just going to these videos. Learned more in 10 minutes than half a semester

[apicciano]

@tfbl928

Thanks for the comment.

Good luck with your work!

Dr. P.

[Kasnopich]

Dr. if it's alright, would you allow me to consult with you with our research paper? your time would greatly be appreciated! thank you!

[keishawoodxxx]

I cannot tell you how help this has been for my stats class...i have an instructor that has completely lost the whole class....I was referred to this video by a class mate and now I think all of us have watched it and feel more confident in what we are learning..thanks again

[apicciano]

@keishawoodxxx

Keisha,

Thanks for letting me know that these videos are of help to you and your classmates.

Best of luck in your studies!

Dr. P.

[TheSolarrock]

Wow this has been so helpful thank-you so much!

[CardNox]

I have a small question. Can I use ANOVA on the following data:

90 respondents who all graded 6 items on a 5 point Likert scale.

I was thinking of use the One way ANOVA but not sure if this is correct. Thanks Dr. P.

[apicciano]

@CardNox

The simple answer to your question is yes. However, if you are just going to summarize the responses to the six items, you can use frequency distributions. On the other hand if you are going to compare responses within the six items, you can use ANOVA or contingency tables (crosstabulations). If you are not familiar with frequency distributions or contingency table, there are videos in my collection that describe them. Also look at measures of central tendency.

Dr. P.

[CardNox]

@apicciano, wow. I don't even get this fast of a reaction from my ''real teachers''.

I made a hypothesis stating that one of the six items is more important than the other five, so I need to check for signifiance. I did make a cross tab and boxplot already. I will check out your other video's also, thank you!

[chikyumi]

Thank you for the very helpful video.

I'm new to SPSS, and have been trying to use it to analze data from a questionnaire I conducted.

I have collected data from three grades (year 1, 2, and 3) and I want to compare them in terms of self-efficacy (based on the results of an 8 item, 6 point Likert summative rating scale). Would ANOVA be appropriate for this, or could you recommend another procedure?

Thank you for your time.

[apicciano]

@chikyumi

A Oneway ANOVA would be most appropriate for what you want to do.

Good Luck!

Dr. P.

[deerubhai]

Thanks ...........

[nao1163]

how do you calculate cohen<s d with these values? Npairs=50 r=0.6 t=3.5

The answer is d=0.44 but i dont know how to get there

[DRJACOBB]

Wonderful stuff. I'd love to see more. THANK YOU, Professor Picciano! =)

[abhishekgupta1103]

thank yor sir for explaining the concept in a simple way. please tell me can i use ANOVA and N way ANOVA when my independent variables have two groups. or if it can only be used with tthree or more groups?

[apicciano]

@abhishekgupta1103

If I understand your question, you can use a form of ANOVA called a Oneway Analysis of Variance when you have two groups.

[onetoonemeeting]

I am working on the performance evaluation of an organization before and after implementation of an ERP. Although I got some idea of ANOVA thru this vedio but i still confused what parameters shud I take to find the difference. Dr. where can I find the such help can you give me some idea to do this.

[foxgirl100]

Dr. P, could u please, please help me with my 2x3 anova?? Can I send u the data. I am stuck!

[zalves2000]

Dr. Picciano thank you for sharing culture! I'm writing the results for my thesis and I have a lot of info, with your videos its now possible to understand what all the numbers and letters mean. You're the man!

[apicciano]

@zalves2000

Thanks for the comment and the best of luck with your studies.

Dr. P.

[acvoils]

this is great! do you have anything on MANOVA's?

[lb5962]

Excellent! Thank you very much. Could you ellaborate on ANCOVA in a video?

[Nahida786]

Thank you very much for sharing this. GOD BLESS YOU

[apicciano]

Thank you for your good wishes. And good luck with your studies.

Dr. P.

[Nahida786]

Thank you very much for sharing the knowledge. GOD BLESS YOU

[koolio1919]

Hi I am doing my final year project the scope of my project is concerned with attribute data (number of circuit defects in the wire harness of a car, number of taping defects in the wire harness etc.) . I am asked by my project advisor to use ANOVA for this project in the analyze phase of the DMAIC and Design of Experiments (DOE) in the Improve phase. i have no idea how to do that for attribute data. I also want to know that is it necessary to use them in the DMAIC philosophy?

Thanks MoIn

[BajanCreation]

im doing my degree in Banking and Finance and this is part of the course of study. Anova seems a bit difficult to understand but ill have to put in alot of work to master these concepts........

[apicciano]

ANOVA is a very important procedure because it is the most popular method of analyzing the mean...stay with it and practice some simple data comparisons and it should become clearer for you

Good luck with your studies!

Dr. P.

[trknigatu]

Well read.

Tariku, Ethiopia

[apicciano]

Thank you,

Dr. P.

[donnayootube]

Thanks a lot!! I'm in a psyc class, and this video is very useful.

[apicciano]

Good luck with your course!

Dr. P.

[Rampenknecht]

Exzellent!

[alifeofgrime]

very good and useful video. keep up the good work!

[FemaleMBAStudent]

It sounded very similar to the books I am reading. I was hoping to find some exaples that we can apply in real life, but thanks for your intention to teach and help.

Rgds,

HR

[morea7]

Would it be fine to run anova on such datasets (which I believe ae much better in terms of varaince similarity and normality) and first of all, is there any way I can find out if the variance and normality situation has improved....

Kindly reply at your earliest convenience.

Thanks

Sincerely

Morea

[morea7]

I have for samples whose mean I want to compare - now the problem is that many values in each sample are '0' and just very few are more that '0' . There were issues also with normality and homogeiety of variance.

What I did was transformed the data by adding 2 to each value and then taking log. That should reduce the variance well enough but I am not sure still about normality.

Further in next comment...

[morea7]

Hello Prof.,

Thank you very much for your educational videos. I have a question about one-way anova and I would be very gateful if you can give some advice on that. Please see next comment..

[nghnino]

Dr. A.G. Picciano Thank you very much for the help, not only me, but the whole world and humanity, who needs special person like you, you also help a lot of Master students who have already their research/ thesis dissertation, thanks for sharing.

[apicciano]

Dear nghnino,

Thanks for your comment. Good luck with your studies.

Dr. P.

[formless777]

Various forms of ANOVA are also used and abused in Psychology :D Thankyou Dr. Picciano for this clip which amounts to a public service for any student grappling with statistics of this sort.

[apicciano]

Thank you for the comment.

Good luck with your work!

Dr. P.

[SayHelloAgaintoMoney]

I am currently working on an ANOVA exercise. ANOVA is very beneficial in financial analysis as well as measuring employee productivity.

[DiamondsOfDublin]

hi there, can you please help me with a topic on ANOVA? If parametric assumptions have not been met, and there in no homogeneity of variance, can a one way ANOVA between subjects test be carried out? if not which test do i use?

Regards

[apicciano]

In most standard statistical software packages such as SPSS, if the variances are unequal then you can use a post hoc analysis procedure with the Oneway ANOVA such as:

Dunnett's T3. Pairwise comparison test based on the Studentized maximum modulus. This test is appropriate when the variances are unequal.

Games-Howell. Pairwise comparison test that is sometimes liberal. This test is appropriate when the variances are unequal.

Good luck!

Dr. P.

[Hipac01]

Just submitted the last assignment for the course. Just got to study for the exam now

[Hipac01]

like wise kchris06, CSU Australia

[apicciano]

good luck with your studies!

[firelovelight]

Do you know how to calculate anova by hand on a calculator? I nee dto know how to get treatment, error, and df an ss and ms and f and i havnt a clue how without a program.

[apicciano]

It is a very complex calculation to do by hand. You will also need a table of f values. I would suggest you consult one of the standard textbooks on education research by L.R. Gay or William Wiersma.

Dr. P.

[greenzx9r]

yes, good post, im doing stats through cqu in qld too.

[kchris06]

thank you for uploading

very useful since I'm doing stats through CSU in Australia

[apicciano]

Good luck with your course.