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How to calculate your ATAR from trial/past paper marks (1 Viewer)

scaryshark09

∞∆ who let 'em cook dis long ∆∞
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+ improved the ATAR calculation a decent amount. after the last update it was underestimating by ≈0.2 on avg at high atars due to the lack of sufficient segmentation in the aggregate->atar conversion and the same issue as the scaled marks with the lack of decimal places on google sheets trends (previously this balanced out because for some reason it increased scaled marks), so I ran it through my program and made a way more accurate formula
You sound like Apple saying their camera on the phone improves each year
 

SadCeliac

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I inserted these equations using a simple IF() formula for whether a student is within that 25th percentile, with both MAX(x,0) and MIN(x,100) functions to prevent an extreme increase/decrease in ATAR although this shouldn't ever really be necessary notwithstanding any errors in the fairly manual data entry process. All of the English scaled marks are then split into individual units and placed in the B column below the calculator. From this list the sum of the best 2 units of English is determined through the sum of a =sortn function which finds the 2 greatest units of scaled marks. Then, for the remaining 8 units needed for calculation, a similar process of unit splitting occurs into column D, and to account for cases in which more than 2 units of English are counted, the worst 4 units out of the six available English units are added to the list using an ascending =sortn function. Similar to the process for English, the sum of the remaining best 8 units is determined through the sum of a =sortn function, which is then summed once more with the best 2 units of English to find the aggregate. Due to the use of =sum(sortn) functions, it isn't immediately visible which units were counted, so I got around this by using another =sortn function (without =sum) which creates a list of counted units in columns E and F (for names and marks respectively), by using two sortn functions (one for English and one for the rest) with an area that includes all of the names and marks for each subject, with the marks as the sorting column, in descending order. The 'Counted units' cell in row 6 for each subject then just employs a simple =COUNTIF check for how many times the name of the subject is included in this sorted list of the top 10 units, with a simple failsafe so that it is equal to 0 where the scaled mark is zero, and equal to 2 when above 2 are present (which can occur for English where less than 10 units are present and it is equal to 0 in some rare cases - unimportant for real calculations but nonetheless included for quality of life). There is also a simple detector for when a 0 is present in the top 10 units list using another =sortn function in ascending order (as a 0 will be the lowest value) which notifies the user that less than 10 units are present.

Finally, the conversion from aggregate to ATAR is percentile-based, so it could not directly be modelled through a quadratic - this produced extreme inaccuracies at high ATAR ranges. I got around this by calculating the quadratics in sections, and found that quadratic formulas were remarkably accurate within small ranges of ~5 data points. Because the UAC data does not extend below 50, I created a simple quadratic by equating an aggregate of 0 to an ATAR of 0 and including the 50 and 55 data points to provide a relatively realistic curve below 50. These equations were then inserted using a simple =IFS formula, with an integrated limitation to provide an * for marks below 30 (both to mirror the HSC and to prevent usage in an area where the calculator is inaccurate), which is then rounded to the nearest 0.05 using an =MROUND function. I considered using more intense rounding below certain ATAR points to remove the pretence of that level of accuracy at low ATARs, but ended up resolving against it to allow usage of the calculator as a tool to track progress. Each of the "ATAR equivalent" cells use this same formula, except with the scaled mark multiplied by 5 or 10 (for 2 and 1 unit subjects respectively) in place of the aggregate.

I definitely plan on adding more years in the future (with a dropdown for each subject), but given the time commitment needed to model each subject it just isn't really feasible, and at the end of the day last year's data is usually going to be the most relevant anyway. Adding more subjects isn't really possible due to the limited available data on rawmarks.info, because I've added every subject with sufficient data.

Some statistics on the aligned->ATAR conversion from some quick testing with some ATARs published on this website + conquer from last year (this is not native functionality, if you want to do this then go into advanced mode and enter them in the "unrounded aligned marks", and make sure you put a number for the raw mark of mx2 so that mx1 counts as 2 units):
- UAC ATAR Calculator had an average delta of 0.1 ATAR points (minimum of 0, maximum of 0.25)
- My ATAR Calculator had an average delta of 0.1 ATAR points (minimum of 0, maximum of 0.2)
- Matrix ATAR Caculator had an average delta of 0.25 ATAR points (minimum of 0.15, maximum of 0.45)

Keep in mind most of the ATARs used were quite high (95-99.5) but this is a bit unavoidable given the dataset on BoS/conquer. Obviously the aligned->ATAR conversion isn't the main part of my calculator but it's accuracy is nonetheless important. It's also just impressive that matrix, a major tutor company with limitless resources has a less accurate calculator than I made fairly easily in a few days.

These tests are outdated - I may retest at a yay?later date as these calculations are significantly more accurate after some improvements.

If you made it this far then thanks for reading and I hope you enjoy the calculator :)

Also if you find any issues or errors please let me know so I can fix them!
Just curious - was HSC 22 an easy HSC year? Like is this something that will (hopefully) accurately reflect our marks and ATAR - OR - is it a hopeful estimate based on data from subjects that aligned like crazy due to hard papers

E.g. if papers aren't as hard this year, more people will do well, and less adjustment will happen (of course to compensate for the easier papers ig) and then ATAR will be lower than estimated 😬

Could someone clarify pleaaaaaase 😣
 

carrotsss

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Just curious - was HSC 22 an easy HSC year? Like is this something that will (hopefully) accurately reflect our marks and ATAR - OR - is it a hopeful estimate based on data from subjects that aligned like crazy due to hard papers

E.g. if papers aren't as hard this year, more people will do well, and less adjustment will happen (of course to compensate for the easier papers ig) and then ATAR will be lower than estimated 😬

Could someone clarify pleaaaaaase 😣
for maths ext 1/2 the papers were definitely harder than usual (and so yes, they did align a fair bit better than usual), english is usually pretty constant, and idk about the rest of your subjects. ideally you want to enter in marks from the 2022 hsc exams or similar difficulty papers, I would add more years but that would actually take days so it’s not happening before the hsc
 

SadCeliac

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I would add more years but that would actually take days so it’s not happening before the hsc
Yeah completely understand lol

Would you do like an average ATAR based on a lot more data or just have a seperate calculator for 2021 data, 2020 data, 2019 data ..etc
 

carrotsss

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How accurate is the calculator if im from a mid 200 ranked school
the only thing this calculator can do is estimate your ATAR based on the raw marks you submit, assuming that your moderated school assessment mark will be identical to your exam mark, you perform the same on the day and that the marks are from 2022 hsc past papers or papers of similar difficulty that have been marked fairly. if you’re ranked first in your subjects then it should be quite accurate, but if you’re not then your internal marks will likely be ≠ your external marks, so if you’re ranked poorly then your actual ATAR will likely be lower, and if you’re ranked well then your actual ATAR may possibly be higher than estimated
 

No surprises

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Could you add English EAL/D and Chinese and literature Pleaseeeeeeeeeeeeeeeeeeeeeeee lysm my god
 

unhealthyharold

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wld you say this is more or less accurate the better your school ranks?
 

SadCeliac

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wld you say this is more or less accurate the better your school ranks?
ranks will probably help no matter what, in the end all of this is just an approximation
better to wait until hsc marks come out lol and then put them into atar compass and matrix and all the other rando ones and then average the estimate

or

just wait until atar comes out
 

unhealthyharold

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ranks will probably help no matter what, in the end all of this is just an approximation
better to wait until hsc marks come out lol and then put them into atar compass and matrix and all the other rando ones and then average the estimate

or

just wait until atar comes out
defo shld just wait but also i need an ego boost or i’m never going to study
 

carrotsss

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wld you say this is more or less accurate the better your school ranks?
if you are ranked well in a good school, then this calculator will likely underestimate your ATAR. If you are ranked poorly in a bad school, then this calculator will likely overestimate your ATAR.

Your moderated school assessment marks make up 50% of your HSC marks and I obviously physically can’t account for them, this calculator just assumes that they’re the same as your aligned exam marks which is unlikely unless you’re ranked first.
 

unhealthyharold

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if you are ranked well in a good school, then this calculator will likely underestimate your ATAR. If you are ranked poorly in a bad school, then this calculator will likely overestimate your ATAR.

Your moderated school assessment marks make up 50% of your HSC marks and I obviously physically can’t account for them, this calculator just assumes that they’re the same as your aligned exam marks which is unlikely unless you’re ranked first.
i’m ranked absolute ass in a top 10 schl so i’m cancelling it out therefore the calculator is 100% accurate 🙏🙏🙏🙏 + thanks for this ur spreadsheet skills are magnificent 😍😍
 

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