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Way Behind (1 Viewer)

kpq_sniper017

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In Maths Ext 1, the difference in marks between 1st and 2nd is 0.8, but then the difference between 2nd and me is 2.7 - the person coming 4th is another 3.2 marks behind me.

Would that mean that at this rate, I'd be affected a fair bit by aligning and moderating?
 

Lazarus

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How many are in your class, and how far below you is the bottom student?

(It will inevitably depend on how your class performs as a whole in the HSC exam.)
 

*girl04*

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serious pc i think it will all be good. you have like only 2 and 3 marks diff. when you said way behind i was thinking like biz studies at our school were the diff is 20 percent no jokes
 

kpq_sniper017

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Originally posted by Lazarus
How many are in your class, and how far below you is the bottom student?

(It will inevitably depend on how your class performs as a whole in the HSC exam.)
in my class there are 9, but in total (including ext 2 students and the yr12s ahead of me) there are 36 i think.
the guy behind me is around 3.2 behind (after weighting - we've done 40% of our assessment)

although, some guys in my class have a "don't care, i'm gonna repeat it" attitude and get around 20% in exams and are around 20 marks behind me.
 

kpq_sniper017

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Originally posted by *girl04*
serious pc i think it will all be good. you have like only 2 and 3 marks diff. when you said way behind i was thinking like biz studies at our school were the diff is 20 percent no jokes
we've only done 40% of our assessment, and so 3 marks is around 7%, so after 100% of the assessments have been done, i'm predicting that the gap will extend to around 7 or 8 - which is way behind :)
 

Estel

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You'd be affected by moderating if your ranks and relative differences weren't preserved in the final exams (naturally).
 

acmilan

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Originally posted by *girl04*
when you said way behind i was thinking like biz studies at our school were the diff is 20 percent no jokes
My software class:
Im on 93ish
2nd Place is on 60
 

Lazarus

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Originally posted by pcx_demolition017
in my class there are 9, but in total (including ext 2 students and the yr12s ahead of me) there are 36 i think.
Mmm, it's the 36 that counts. Being ranked second in a group that large effectively severs any connection between your moderated mark and the rest of the class - your moderated mark will float up and down with the top examination mark. You'll want to make sure that the latter is as high as possible.

Originally posted by pcx_demolition017
although, some guys in my class have a "don't care, i'm gonna repeat it" attitude and get around 20% in exams and are around 20 marks behind me.
Those students will only adversely affect you if they perform worse in the HSC exam than what was to be expected on the basis of their assessments. Obviously, you'll be benefited if they perform better (so share your notes with them after your assessments have been finalised ;)).
 

kpq_sniper017

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Originally posted by Lazarus
Mmm, it's the 36 that counts. Being ranked second in a group that large effectively severs any connection between your moderated mark and the rest of the class - your moderated mark will float up and down with the top examination mark. You'll want to make sure that the latter is as high as possible.

Those students will only adversely affect you if they perform worse in the HSC exam than what was to be expected on the basis of their assessments. Obviously, you'll be benefited if they perform better (so share your notes with them after your assessments have been finalised ;)).
not a bad idea :)

someone in yr12 told me (and i haven't verified whether it's true or not) that last an ext 1 student had an internal assessment of around 30% and yet gained an aligned mark of 90 (or 45). the difference between him and the top guy was apparently around 50-60%. can this actually happen, coz it just doesn't seem likely.
 

Lazarus

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Originally posted by pcx_demolition017
last [year] an ext 1 student had an internal assessment of around 30% and yet gained an aligned mark of 90 (or 45). the difference between him and the top guy was apparently around 50-60%. can this actually happen, coz it just doesn't seem likely.
You people can really make your figures confusing sometimes. I'll just convert everything to percentages and work from that, okay?

At first glance, the scenario seems possible. Let's assume that it is, and for the sake of simplicity, that there were only three students in the class - the third student was ranked last (with an unknown mark).

So:

[1] Joe Bloggs was ranked 2/3 with an internal mark of 30%.
[2] The top guy was ranked 1/3 with an internal mark of 80%.
[3] Joe ended up with a moderated mark of 90%.

We can deduce that:

[4] The difference between the internal marks of Joe and the top guy was 50% (from [1] and [2]).
[5] The bottom internal mark was less than or equal to 30% (from [1]).
[6] The top exam mark was above 90% (from [3]) - and probably far above, so let's say 100% (for simplicity).

We can also deduce from those deductions that:

[7] The difference between the moderated marks of Joe and the top guy was equal to 10% (from [3] and [6]).

Finally, we define some variables:

B<sub>i</sub> = the bottom internal mark
B<sub>e</sub> = the bottom exam mark
J<sub>e</sub> = Joe's exam mark

D<sub>i</sub> = the difference between Joe's internal mark and B<sub>i</sub>
D<sub>i</sub> = 30% - B<sub>i</sub>

D<sub>e</sub> = the difference between Joe's exam mark and B<sub>e</sub>
D<sub>e</sub> = J<sub>e</sub> - B<sub>e</sub>

Now, the moderating procedure should generally preserve the relative differences between students. Therefore in order for the 50% difference between Joe and the top guy to be compressed to a difference of 10%, D<sub>i</sub> must have been compressed by the same factor to become D<sub>e</sub>. Other factors would fail to preserve the relative differences between students.

i.e. -
50/10 = D<sub>i</sub> / D<sub>e</sub>
5 = D<sub>i</sub> / D<sub>e</sub>
D<sub>e</sub> = D<sub>i</sub> / 5

Substituting for D<sub>e</sub>:

J<sub>e</sub> - B<sub>e</sub> = D<sub>i</sub> / 5

J<sub>e</sub> = (D<sub>i</sub> / 5) + B<sub>e</sub>

Substituting for D<sub>i</sub>:

J<sub>e</sub> = [(30% - B<sub>i</sub>) / 5] + B<sub>e</sub>

Now, we want information regarding the situation where J<sub>e</sub> = 90%.

Substituting, simplifying and rearranging the above:

B<sub>e</sub> = (420 + B<sub>i</sub>) / 5
B<sub>e</sub> = 78 + 0.2 * B<sub>i</sub>

We impose the following constraint (from [5]):

0 ≤ B<sub>i</sub> ≤ 30%

We can use this to define a valid range for B<sub>e</sub>:

78% ≤ B<sub>e</sub> ≤ 84%

So, given that the bottom internal mark falls within the range (0%, 30%), Joe will receive a moderated mark of 90 where the bottom exam mark falls within the range (78%, 84%), and both marks satisfy the equation B<sub>e</sub> = 78 + 0.2 * B<sub>i</sub>.

I'm sorry for including all of that maths. I got a bit carried away. I (effectively) finished my uni exams today, and had far too much spare time. I think I'll go out.

In short... yes. :) The bottom exam mark just needed to be 78 more than one fifth of the bottom internal mark. The class of three students is really a special case (and could have been determined much more simply, but derivations are more enlightening), but it's possible. A number of other factors can also come into play to limit those ranges further (e.g. enforcing the requirement that the conversion curve is monotonic over the range of the internal marks - if a stationary point occurs in that range, student's ranks would be changed).

You could have also tested it yourself (www.boredofstudies.org/moderate.php). :)
 

Survivor39

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OMG Laz......................:eek: :eek: :eek:
How many exams did you have?
 

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I had one last Friday, one yesterday (Monday), and one today (Tuesday).

It was a little hectic... my last one is next week. It's only AI though and should be relatively easy. :)
 

kpq_sniper017

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Originally posted by Lazarus
In short... yes. The bottom exam mark just needed to be 78 more than one fifth of the bottom internal mark. The class of three students is really a special case (and could have been determined much more simply, but derivations are more enlightening), but it's possible. A number of other factors can also come into play to limit those ranges further (e.g. enforcing the requirement that the conversion curve is monotonic over the range of the internal marks - if a stationary point occurs in that range, student's ranks would be changed).

You could have also tested it yourself (www.boredofstudies.org/moderate.php).
ok, ic.
so basically, the only way that can happen is if the guy at the bottom still does well in the final exam. otherwise, it wouldn't happen. now i understand the reasoning behind helping people after the internal assessments are over :)
 

Lazarus

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That's pretty much right - but remember it's not just the bottom student.

If you had a large class, and you managed to get the student ranked last to improve significantly, that'd be great, but the student ranked second-last would still be pretty low... so they need to improve too... and, well, in reality, you want the whole class to do as well as possible. :)
 

kpq_sniper017

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Originally posted by Lazarus
That's pretty much right - but remember it's not just the bottom student.

If you had a large class, and you managed to get the student ranked last to improve significantly, that'd be great, but the student ranked second-last would still be pretty low... so they need to improve too... and, well, in reality, you want the whole class to do as well as possible. :)
that's gonna be a pretty tough job.
the guys in my class are gonna repeat and some r gonna do ext 2, so they don't care. but it would be tough to get them to do better :)
at least the guys in yr12 will probably do well, coz they have an incentive.
the guys in my class need a reward (like $1000) or something before they'll do work (apart from a few)
 

CrashOveride

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hmmmm....if your ranked 1st doesnt that effectively neutralize any kind of scaling ??
I was asking teachers and they didnt know $h!t, one said like the gap difference also matters, even if ur coming 1st ??
 

Ragerunner

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When you are ranked first you are basically given total immunity to scaling. It is always that you receive the highest HSC examination mark as your moderated assessment mark.
 

kpq_sniper017

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Ragerunner said:
When you are ranked first you are basically given total immunity to scaling. It is always that you receive the highest HSC examination mark as your moderated assessment mark.
what if 1st, 2nd and 3rd are within close proximity of each other e.g. 0.5 between 1st and 3rd? would there much of an advantage in coming 1st? would u be scaled much if u were coming 3rd?

btw. to what degree of accuracy are internal assessments marks reported to the BOS? 0.1, 0.01?
 

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