Multiple Regression Question?

Sep 06 2012 Published by under Ranking In Google

Question by : Multiple Regression Question?
please help:

For a multiple regression with three explanatory variables the value of R2 is 0.75.

Indicate whether each of the following statements is true or false and give brief reasons for your answer:

(i)The three explanatory variables each explain 25% of the variation in the dependent variable.

(ii)If R2 = 0.75 then three quarters of the data is perfectly explained by the model.

(iii)The most important factor when comparing this model with any others is to find the highest R2.

(iv)The higher the value of R2, the greater the probability the model is correct.

Explain the difference between the usual (product moment) correlation and rank correlation. In what situations is it more appropriate to use rank correlation?
(30 marks)

Best answer:

Answer by cidyah
i) The three explanatory variables each explain 25% of the variation in the dependent variable.

Not true. The three variables as a whole account for 75% of the variation in the dependent variable.

(ii) If R2 = 0.75 then three quarters of the data is perfectly explained by the model.

Not true. 75% of the variation in the entire data is explained by the model.

(iii) The most important factor when comparing this model with any others is to find the highest R2.
True. We want the R^2 to be as large as possible so we can expain the variation in the dependent variable at best by using the three independent variable.

(iv) The higher the value of R2, the greater the probability the model is correct.
you may want to go through the link.

Product moment correlation measures the strength of linear association between two variables. Rank correlation is nonparametric that it can be used for ordinal data whereas Pearson correlation requires that they be interval or ratio scaled data. When we compare the degree of similarity of two rankings, (two judges judging the contestants of a contest), rank correlation is more appropriate. Product moment correlation requires bivariate normality assumption whereas the rank correlation doesn’t.

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Q&A: How can I SEO my blog?

Jan 23 2012 Published by under SEO

How To SEO
by IvanWalsh.com

Question by Robina: How can I SEO my blog?
I am unable to get traffic to my wordpress blog even after getting plugins installed. What should I do?

Best answer:

Answer by Mubashar Abrar
You can do seo by using all in one seo plugin for wordpress. It take time to seo your blog. Forr more info go to the site below:

Know better? Leave your own answer in the comments!


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How to get a job as a SEO?

Dec 26 2011 Published by under SEO

How To SEO
by New Media MK

Question by pooky: How to get a job as a SEO?
I already have a business degree but only sales/ customer service experience. I would like to become a SEO search engine optimisation. Do I need a new qualification? what are the best entry levels?

Best answer:

Answer by Jan409
People who do SEO usually work within an I.T. company or business and have other roles too
my son does S.E.O. but also runs his own business doing web design, repairs and a million other things
S.E.O. is only a part of the total I.T. function for him

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3 responses so far

How do you start a SEO business?

Dec 11 2011 Published by under SEO

Question by Tibby: How do you start a SEO business?
What do you need to learn, how much can you make?

Best answer:

Answer by CmsBuffet.com
Build a web site for your business.
Read and learn SEO
Apply to your web site
if you are doing well try to persuade other businesses to give you their web site.

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Is there any Internet Marketing guru who would be happy if I promoted his successful internet money maker?

Sep 01 2011 Published by under SEO

Question by Bruno: Is there any Internet Marketing guru who would be happy if I promoted his successful internet money maker?
As long as you are a genuine internet marketing guru, webmaster or seo specialist with your genuine money making internet or ecommerce business, I would be happy to start learning from your experience and knowledge by simply promoting your successful online money making system and of course making my money out of it.
Please, understand I am an absolute beginner (not a fool though) in this field and tell me what you have to offer and how we could start working and making money together.
Many Thanks and God Bless!

Best answer:

Answer by chunkifeat
Check out http:// www.perrymarshal.com. Buy his book “the ultimate guide to adwords”, and look into his on line e-book “the definitive guide to adwords”. There are a lot of clowns in the internet marketing game. Marshal’s not one of them. Be cautious.

http://www.perrymarshal.com

PS: Beware of any web site with pictures of guys holding wads of cash. Chances are, the cash they are holding come from people like you.

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Q&A: how much should i pay per month for seo services -and what should i expect them to do?

Jul 17 2011 Published by under SEO

Question by crunchynutcornflakes: how much should i pay per month for seo services -and what should i expect them to do?
multi instrumentalist wanting to sell my music to various clients,radio stations,adverts ,films etc

Best answer:

Answer by quickies
You can pay if you wish but there are lots of ways you can do most of it yourself.
If your website is already set up you will probably need to alter a few things in order
have it optimised e.g.. your keywords
your content should include your chosen keywords in your title, subtitle and articles.
an introduction that describes your main theme.
This would include several of your top keywords and keyword phrases.
Repeat your top 1 or 2 keywords several times, include other keyword search terms too, but make it read in sentences that make sense to your visitors.

Key words are the most important part of seo as these are what tell the search engines
what your site is all about.
It can be quite expensive to hire seo experts if you are just starting out

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How to better promote business websites online (SEO)?

Jun 20 2011 Published by under SEO

Question by Art D: How to better promote business websites online (SEO)?
My company operates a business in the U.S. under http://www.artdriver.com. Now it starts operations in the UK and recently launched a UK based website – http://www.artdriver.co.uk. In terms of SEO: Is it better to have two separate websites or keep everything under one domain name? thanks

Best answer:

Answer by Julz
it would be best for the uk site to have a uk domain and the us on have its own also as it would be less confusing for customers…

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Q&A: How easy is it to SEO your own web site?

May 26 2011 Published by under SEO

How To SEO
by BrentDPayne

Question by Tao: How easy is it to SEO your own web site?
And if yes how do I do this please. Laymans terms please not PC literate

Best answer:

Answer by Ms. Intrigued
SEO for Dummies will help you, these are often simplified for the beginner so a good place to start

http://www.bigmarketingsmallbusiness.com/2006/09/26/seo-for-dummies-demystifying-optimization/

plus add your URL to google

http://www.google.co.uk/addurl/

Add URL to Yahoo

http://search.yahoo.com/info/submit.html

Add your URL to all major search engines.

http://www.20search.com/

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how do i send a fan letter to the japanese author seo kouji?

May 24 2011 Published by under SEO

Question by Sola Chu: how do i send a fan letter to the japanese author seo kouji?
am a really big fan of his work and i want to write that he inspired me to do alot fings, :)

Best answer:

Answer by James
The best way would be through his publisher. If an American through the American publisher if British the British publisher and so forth. They can either forward it or give you an e-mail contact. You might also check the back of one of his books and see if there is a e-mail address listed there.

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SPLUS warning message of the day- what does this mean?

May 23 2011 Published by under Ranking In Google

Ranking factors
by UggBoy♥UggGirl [ PHOTO // WORLD // TRAVEL ]

Question by Angela C: SPLUS warning message of the day- what does this mean?
I’ve read textbooks and surfed the interwebs, but I actually get answers here….
I’m running the step() function on some models and sometimes it’ll run allthe way through, sometimes it seems not to start and sometimes it looks like it runs part way. This is the message I get on the latter 2:

Step: RFPE = 59.6287
NY.RANK ~ MIX.USE + GAR + OCCUPANT + IS.FLAT + toBstop50 + centT50 + tr50.10min

Warning messages:
Initial scale less than tl = 1e-006 . in: lmRob.fit.compute(x2, y, x1 =
x1, x1.idx = x1.idx, nrep = nrep, robust.control ….
Problem in .Fortran(“s_psiamm”,: subroutine s_psiamm: 134 Inf value(s) in argument 2

Where is the infinite value coming from? What exactly does that mean? And is it really a problem if I can still get a multiple R squared using the summary() function on the same model?

NY.RANK,toBstop50,centT50 are doubles; MIX.USE, GAR, OCCUPANT, IS.FLAT are binary factors; tr50.10min is an integer (though on a whim I’ve tried it as a double, too). The model was built with lmRob, na.action=na.exclude. All the columns have varied values (i.e. I don’t have any columns that are all 0 or all 1, etc).

Any ideas?

Thanks

Best answer:

Answer by Vincent G
This message comes from the program itself. Knowing exactly what it means depends on what the program is doing and however it was programmed.
There would be an infinite value if something large was divided by something very tiny, In this case, it may be something like a returned function not changing at all between two steps, and having a ‘flat slope’ the reciprocal thereof being infinity.
To know more would require looking at the source code.

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