Is SAM accurate?? (1 Viewer)

Kate_J

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The mean was off by 5.45.
If only I did the HSC in 2001 I would have almost 10 more points!
 

Karlz04

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tia6 said:
The mean was off by 5.45.
If only I did the HSC in 2001 I would have almost 10 more points!
Same, I wish I was class of 01! That extra 10 would be very nice. It was off by about 7 for me.
 

KeypadSDM

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dprs said:
To the person who got 60 something in SAM and achieved 90 something... maybe you entered in your raw marks?

SAM said I would get 99.9, using my final HSC marks from the BOS, and i ended up getting 99.8

so its pretty accurate I guess, considering the scaling trend ;)
Actually, that's hideously innacurate. It put you at top 100 people, you got top 180. That's massive.
 

Templar

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People do have to disregard the UAI for 2001 seeing it was the first year and people didn't know what to do.

SAM is like any prediction, it's not an exact science. How accurate it is depends on the change in data from year to year.
 

Fuzznutt

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My Uai Was Predicted Perfectly

When I got my HSC allinged marks on the 17th, I punched them into SAM and it gave me 82.35 in 2003. The next day, I recieved a 2004 UAI of 82.35. SAM was 100% accurate!!!!!!!
 

Lainee

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I think I posted this on a similar thread before... but SAM estimated 99.5 for me, and that was exactly what I got.

I'm a bit confused about one thing though. I went back to school yesterday and one of the teachers were trying to estimate UAIs based on the scaling report and the grade's HSC marks that the school gets. After taking into account my 10 highest units, my aggregate was shown as 452, which isn't too far off from 99.5 (based on SAM's aggregate of 458 giving me 99.5). How was it possible for him to calculate this without knowing raw marks? He also said that it would've been possible for me to figure this out myself - and if this is so, how would I go about doing it?
 

Lazarus

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Ideally, if you wanted to do the calculations properly, you would start with your aligned HSC marks, 'unalign' them to get your raw HSC marks, and then scale those raw HSC marks to get your scaled marks.

However, we can't do this because no data concerning raw marks is published.

The preliminary scaling report includes tables which provide a set of equivalences between aligned HSC marks and scaled marks, allowing us to skip steps involving raw marks. Check out Table A3 and you'll see what I mean.
 

holdenarum

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Frigid said:
speaking from my own set of marks, SAM had a position variance of UAI 0.10, which seems very reasonable :)
not very accurate for my UAI- out by a full 5 marks of the average on sam. not happy john
 

flipsyde

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SAM underpredicted my UAI by 35 marks... Really had me worried... which means I killed in the HSC....
 

Lazarus

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flipsyde said:
SAM underpredicted my UAI by 35 marks... Really had me worried... which means I killed in the HSC....
Uhh... is this because you underpredicted your own marks, or did you enter in your actual HSC marks and receive a UAI up to 35 points below your actual UAI?

Would appreciate it if you could post your input to the program.
 

miffytoki

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during the year i think i entered the marks on my report...SAM estimated sumthin like 91. _ ...after HSC i entered my HSC final marks thingy and SAM estimated 97.75....and when my UAI came out i got 97.6
 

Lazarus

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flipsyde said:
entered exactly what was on my report
You can't just enter your school marks - SAM only accepts aligned HSC marks (the ones reported by the Board).

We've been warning students about that all year. Obviously, not well enough.
 

Estel

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In defence of SAM

SAM by nature can't be entirely accurate even for the year given.
As an example:
In 2003 student A and B get:
80/100 in 3U Maths, 4U Maths, 2U English, 3U English, 4U English, 2U Modern History.
One student could get 90.45 and another could get 91.4. How is SAM meant to get both right? You can only guess that you got somewhere in between. [79.5 and 80.4 will both show up as 80]

This doesn't even begin to think about different distribution of HSC marks for different years and changing candiditures.
Then be nice and give SAM a small margin of error.

So if SAM is 1.5 off, don't whinge about it.
SAM is a nice fun little toy.

Edit: Plugging what would appear to be the same marks of 2 students across 2 years in SAM, I managed to generate UAI's 4.5 apart. This is by no means the maximum range of error, and this is assuming SAM is 100% accurate.
 
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gordo

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sam predicted by 04` UAI exactly. (once i had typed in my official hsc aligned marks)

credit where credit's due
 

melsc

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all the pplz complaining in the end it is an ESTIMATION....use it as a guide...a girl in my skool was silly enough to drop a subject bcoz something to do with Sam...i reckon SAMS great but u cant expect it to b perfect!!!
 

jm1234567890

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melsc said:
all the pplz complaining in the end it is an ESTIMATION....use it as a guide...a girl in my skool was silly enough to drop a subject bcoz something to do with Sam...i reckon SAMS great but u cant expect it to b perfect!!!
well, i wouldn't call it stupid.

it is there as a guide, if you don't make use of the info a guide gives what is the point of using it in the first place.

i guess she should have talked to teachers as well.
 

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