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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Mathematical Methods CAS => Topic started by: happyhappyland on September 05, 2010, 10:00:13 pm

Title: Study score I would have gotten
Post by: happyhappyland on September 05, 2010, 10:00:13 pm
I just did 2008 Exam under timed conditions and got

27/40 = 54/80 for exam one equates to a B+
63/80 = 126/160 for exam two that is around a mid A

My sacs would been a mid A aswell. What study score would I have gotten?
Title: Re: Study score I would have gotten
Post by: RainerWolfram on September 05, 2010, 10:02:49 pm
35 - 36
Title: Re: Study score I would have gotten
Post by: _avO on September 05, 2010, 10:09:49 pm
27/40 would have just scraped B+ and 63/80 is the highest A

So according to the stats ('08) it would equate to approximately:
EXAM 1 = 11 x 0.51 (you're percentile) = 5.61/11
EXAM 2 = 22 x 0.885 = 19.47
SAC = 17 x 0.73 = 12.41
Total = 5.61 + 19.47 + 12.41
        = 37.49 SS
that would be my estimation but it could vary from 35~38
Title: Re: Study score I would have gotten
Post by: happyhappyland on September 05, 2010, 10:14:15 pm
27/40 would have just scraped B+ and 63/80 is the highest A

So according to the stats ('08) it would equate to approximately:
EXAM 1 = 11 x 0.51 (you're percentile) = 5.61/11
EXAM 2 = 22 x 0.885 = 19.47
SAC = 17 x 0.73 = 12.41
Total = 5.61 + 19.47 + 12.41
        = 37.49 SS
that would be my estimation but it could vary from 35~38

Thats some pro stuff there.. did you work out my percentile using normalcdf with the mean and sd on the statistics page?
Title: Re: Study score I would have gotten
Post by: _avO on September 05, 2010, 10:19:04 pm
Nah no methodsy stuff xD just looked at the table they give on the stats page and added the total % of people who would have done better then 27/40 and multiplied it with 22%(GA2) x 50(ss). Did similar thing to the other 2 estimates
Title: Re: Study score I would have gotten
Post by: f.sharp on September 05, 2010, 10:34:00 pm
losing 13 marks on a methods exam 1 is unforgivable :P
Title: Re: Study score I would have gotten
Post by: f.sharp on September 06, 2010, 11:21:58 pm
decided to give this exam a go :)

exam 1- 40/40
exam 2- 77/80

given im ranked sumwhere in the top 10 or 15ish of a really strong cohort of 150 or so kids, wat kind of ss would i get?
Title: Re: Study score I would have gotten
Post by: letsride on September 06, 2010, 11:25:47 pm
47+
Title: Re: Study score I would have gotten
Post by: taiga on September 06, 2010, 11:48:16 pm
decided to give this exam a go :)

exam 1- 40/40
exam 2- 77/80

given im ranked sumwhere in the top 10 or 15ish of a really strong cohort of 150 or so kids, wat kind of ss would i get?

37
Title: Re: Study score I would have gotten
Post by: Hutchoo on September 07, 2010, 12:03:50 am
decided to give this exam a go :)

exam 1- 40/40
exam 2- 77/80

given im ranked sumwhere in the top 10 or 15ish of a really strong cohort of 150 or so kids, wat kind of ss would i get?

37
45+

37? Lolwut
Title: Re: Study score I would have gotten
Post by: TrueTears on September 07, 2010, 12:06:25 am
decided to give this exam a go :)

exam 1- 40/40
exam 2- 77/80

given im ranked sumwhere in the top 10 or 15ish of a really strong cohort of 150 or so kids, wat kind of ss would i get?
According to 2008, you would get 50. (I was told dcc lost 3 marks and got 50, but I know for sure losing 2 marks yielded a 49 my friend got 49)

According to 2009, you would get 48. (I lost 3 marks and got 48, my friend lost 2 and got 49)
Title: Re: Study score I would have gotten
Post by: f.sharp on September 07, 2010, 12:13:39 am
sweet, thanks :)
Title: Re: Study score I would have gotten
Post by: Mao on September 07, 2010, 02:47:18 am
@avo & happyhappyland

Have a look here: http://vcenotes.com/forum/index.php/topic,6688.0.html
You might be interested in the maths going on there.
Title: Re: Study score I would have gotten
Post by: happyhappyland on September 08, 2010, 09:01:47 pm
@avo & happyhappyland

Have a look here: http://vcenotes.com/forum/index.php/topic,6688.0.html
You might be interested in the maths going on there.

I never seemed to have used that excel document properly, but for me Ive worked out somethign with probability Ive learnt from methods...

Say for an easier subject like Chemistry
Get a total out of 50 so
33% of 50 for each thus each GA is worth ~16.5 marks.

You enter ur predicted score into your calc using normalCDF with say 0 to [given score] with the given SD and Mean. X that number by 16.5 and ull get something over 50. But since 40/50 isnt top 10% but top 8% I used basic chemistry-like ratios... Heres an example.

Chemistry 2009 Data
Exam 1: 114/146 GA1
Thus
Lower: 0
Upper: 114
SD: 30.1
Mean: 73.8
NormalCDF= 0.902044856


GA2
190/200
Lower: 0
Higher: 190
SD:31.1
Mean: 151.9
NormalCDF: 0.8897270136


GA2:
140/152
Lower: 0
Upper: 140
SD:33.3
Mean: 88.8
NormalCDF = 0.9340887544


add up all the percentages and average it 0.908620208

then if 40ss=0.92 (top 8%)
"x"ss = 0.908620208

39.5 ss. But you see its not exactly THAT accurate. . Only if the Mean and SD is provided for the actual STUDY SCORE itself. In which in MAO's post you stated

Mean=30 SD = 7

so if i did invNormCDF "L" (left) and the prob was .9086 with SD=7 Mean=30

I get 39.3  But remember the stats I used was
GA1: Lowest A+
GA2: Mid A+ (but mid A+ for sacs is around top 12%)
GA3 : Low-mid A+

So even with 3A+ you get around a 39-40 if one of your A+ is the lowest.
Title: Re: Study score I would have gotten
Post by: Blakhitman on September 29, 2010, 03:02:03 am
What SS would this equate to? (2006)

Exam1-39
Exam2-78
Title: Re: Study score I would have gotten
Post by: 8039 on September 29, 2010, 04:21:31 am
What if I have extremely low SAC marks? failed 2 SACs, one being an application task worth 13% of total study score supposedly and the other a small 3%-er but lowering my ranking nonetheless. I failed the first semester and outranked by about 9 people. I've kinda shot up getting top mark in the most recent SAC and aiming to do the same for the next.

Atm I see myself getting the highest result in the exam of my cohort, realistically a B+ for both or A+ god willing. What's the best I can hope for?
Title: Re: Study score I would have gotten
Post by: kepal5 on September 29, 2010, 09:10:28 am
Can someone predict my study score. I got 73% for Unit 3 and if I get like 83% for Unit 4 and around 85% for each exam what study score would i get around?