do i understand scaling? (1 Viewer)

cem

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The markers who determine the cut-offs are called judges and they do NOT determine the aligned marks for all marks. They determine the cut-offs e.g. 83.1 = 90, 66.3 = 80, 48.4 = 70, 32.9 =- 60, 18.3 = 50 (these are totally made up off the top of my head).

The reason for the .9s etc is that there are 6 judges for each subject and their suggestions are totalled and averaged so if there are 7 sections (as in Modern History - 3 parts for Core, 2 for personalities, and then the 2 essays) these marks are added and divided by 6 to reach the final cut-off.

The .6 etc are important as students exams are doubled marked so it is possible to get .5 as a final raw mark our of 100 and that can then make the difference between bands e.g. student A gets 167/200 and student B gets 166/200 which when converted to a mark /100 = 83.5 and 83 respectively but the cut-off is set at 83.1 meaning that Student A would get 90 but Student B would get 89.

Having determined the cut-offs for the Bands the computers take over and do the aligning between the cut-offs.
 

micuzzo

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no one understands scaling... not even the judges... when scaling is mentioned no one execpt the 'authorised personnel' gets a straight answer... its like their is a thick dark fog over this topic and i think its meant to be that way for a reason... also i believe this process changes every year.


P.s: the above may be an extremely biased and cynical view...but thats my storey and im stickin' to it!
 

Dragonmaster262

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micuzzo said:
no one understands scaling... not even the judges... when scaling is mentioned no one execpt the 'authorised personnel' gets a straight answer... its like their is a thick dark fog over this topic and i think its meant to be that way for a reason... also i believe this process changes every year.


P.s: the above may be an extremely biased and cynical view...but thats my storey and im stickin' to it!
You sound like the teachers in my school lol. That's what they always say, that nobody really knows how scaling works. That's why I joined this site: I wanted to learn how scaling worked. Even my Career adviser seems to have poor knowledge of how the scaling process works (he thinks that Visual Arts and Physics scale the same). There are quite a few things that I don't understand such as how is standard deviation used? What is the scaled mean used for?
 

dp624

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ROFL phys and Va scaling the same!
Scaled mean compares the strength of different cohorts. In general, the higher the scaled mean of a subject, the better its scaling
 

Dragonmaster262

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dp624 said:
ROFL phys and Va scaling the same!
Scaled mean compares the strength of different cohorts. In general, the higher the scaled mean of a subject, the better its scaling
Do you know what Standard Deviation is used for in scaling?
 

Lazarus

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Dragonmaster262 said:
Do you know what Standard Deviation is used for in scaling?
I can answer this relatively concisely, but explaining it might take a bit longer.

The scaled standard deviation for a course is a measure of the spread of the standardised raw marks achieved by its candidature in all of their courses prior to scaling.

Since 2002, there have been two types of scaled standard deviations - initial and final. I have described the initial scaled standard deviation above.

In courses where the top scaled mark is less than the (previously calculated) maximum possible scaled mark, the initial scaled standard deviation is multiplied by a constant to widen the spread of the scaled marks so that the top scaled mark reaches the maximum possible scaled mark. This is the final scaled standard deviation that appears in the Technical Committee's reports.

I personally have a bit of an ideological issue with this post-scaling tweaking of the scaled standard deviation, because the mathematics which underpins the scaling algorithm is premised in a very fundamental way on marks being scaled according to the means and standard deviations produced by the equations. But tweaking occurs. It is at least objective tweaking.
 

dp624

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How is the maximum possible scaled mark determined?
For example, for each of my subjects it's 100. But what about, say, General Maths, where it's about 95? Do they determine the 95 arbitrarily?
 

Lazarus

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It's linked to the combined English candidature - presumably because that candidature includes almost the entire cohort.

See e.g. p17 of the 2007 report at [3.2.6].
 

Dragonmaster262

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Lazarus said:
I can answer this relatively concisely, but explaining it might take a bit longer.

The scaled standard deviation for a course is a measure of the spread of the standardised raw marks achieved by its candidature in all of their courses prior to scaling.

Since 2002, there have been two types of scaled standard deviations - initial and final. I have described the initial scaled standard deviation above.

In courses where the top scaled mark is less than the (previously calculated) maximum possible scaled mark, the initial scaled standard deviation is multiplied by a constant to widen the spread of the scaled marks so that the top scaled mark reaches the maximum possible scaled mark. This is the final scaled standard deviation that appears in the Technical Committee's reports.

I personally have a bit of an ideological issue with this post-scaling tweaking of the scaled standard deviation, because the mathematics which underpins the scaling algorithm is premised in a very fundamental way on marks being scaled according to the means and standard deviations produced by the equations. But tweaking occurs. It is at least objective tweaking.
Standard deviation is so confusing. Oh well, I'll just have to wait until I do it in class. You do get to do standard deviation in the Preliminary course don't you? I remember doing it in Year 9 but I only learnt how it was calculated and not really what it did.
 

Lazarus

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Dragonmaster262 said:
Standard deviation is so confusing. Oh well, I'll just have to wait until I do it in class. You do get to do standard deviation in the Preliminary course don't you? I remember doing it in Year 9 but I only learnt how it was calculated and not really what it did.
I know statistics is covered in the general course, but I can't recall whether it's formally part of the 2U/3U syllabus.

You can find some simple explanations via Google - e.g. here.
 

Dragonmaster262

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Lazarus said:
I know statistics is covered in the general course, but I can't recall whether it's formally part of the 2U/3U syllabus.

You can find some simple explanations via Google - e.g. here.
Thanks for the link. It helped a lot.
 

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