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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE General & Further Mathematics => Topic started by: Respect on March 20, 2011, 01:20:33 pm

Title: Beware! - Of 2006 vcaa II exam Core.
Post by: Respect on March 20, 2011, 01:20:33 pm
a hard exam, I reccomend u study it well. Everything from hard explaining questions, to three median lines, which have 15 points. Which after repeating the course, i still dont know how to do.

Can someone show me how to do, Questions  3.

thanks.

I feel sorry for 2006 further maths students, although, who really cares lol :P
Title: Re: Beware! - Of 2006 vcaa II exam Core.
Post by: _avO on March 20, 2011, 01:50:39 pm
Quote
Firstly split the data in 3 sections

Next find the median of the data in all 3 sections

Then find the gradient of the equation (use the median of the lower and upper sections)

Sub in all the information you found in the formula
c = 1/3[(yL + yM + yU) - m(xL + xM + xU)]; where c=y-int ,L=lower, M=middle, U=upper and m=gradient

Lastly substitute c and m in y=mx+c
that will get you your three median line

the question regarding why using a three median line over a least squares regression line is better is because the three median line is not affected by extremities such as that one outlier (whereas the least squares reg line will be affected), so it will give a more accurate equation to model the relationship of X and Y
Title: Re: Beware! - Of 2006 vcaa II exam Core.
Post by: Shannon101 on March 22, 2011, 09:04:01 pm
Question 3 from the 2006 exam is one of the problems I go through as a practice example in the video tutorial on how to do three median regression. Have a look at that tute; I run through this question step by step. If you're still a bit confused about how to do the a three median regression line, maybe watch the theory tutorial video on that topic. That runs through how to apply this method of regression from start to finish.

Hope that helps!
Title: Re: Beware! - Of 2006 vcaa II exam Core.
Post by: Respect on March 24, 2011, 09:00:32 pm
Quote from: Shannon101 on March 22, 2011, 09:04:01 pm
Question 3 from the 2006 exam is one of the problems I go through as a practice example in the video tutorial on how to do three median regression. Have a look at that tute; I run through this question step by step. If you're still a bit confused about how to do the a three median regression line, maybe watch the theory tutorial video on that topic. That runs through how to apply this method of regression from start to finish.

Hope that helps!


thanks dude, i actually understood it, - the voice of the teacher was alot more entertaining than my teacher lol .