There’s something really screwed up with the College Board’s Section concordance tables on pages 3 & 4
https://collegereadiness.collegeboard.org/pdf/psat-nmsqt-preliminary-concordance-tables-2015.pdf
Page 3 shows the conversion from:
2014 → 2015
Page 3 shows the conversion in the other direction:
2015 → 2014
The page 3 tables do NOT jibe with the page 4 tables. Here is an example:
The very first pair of scores on page 3 show:
2014 → 2015
80…………38
But on page 4, it’s impossible to get back to “80” because the highest corresponding score for a 38 is only “79”
The same problem follows with the other 2015 section scores—you can’t get back to the 2014 high end score. A lot of the problem stems from the fact that the 2015 test which is scaled to 38 simply does not have the same gradational discrimination as the prior tests which were scaled to 80.
I wonder how this clumsy, blunt scaling is going to impact the determination of NMSF cutoffs. My sense is that a lot of people are going to be robbed…
@GMTplus7 38 coverts to a median value of 79.
The 80 converts to a 38. But so do 79 and 78. A few days ago I had commented that what we don’t have are decimals from 38 to 37. Thus it’s quite possible that 80 converts to a 38.4, 79 to a 38.0 and 78 to a 37.6 and all rounded to 38. Best to have the decimals and then round the final answer, I think. On the other hand, this 38 scale isn’t so different from the ACT. I think the issue is that everyone is so used to seeing the PSAT/SAT more finely scaled than it will be going forward.
Edit/Update: I just thought of something that “looks” more reasonable even though it’s a trick and doesn’t change anything. Divide the old PSAT scores by 2 and you’ll see that it’s 40 - 39 that converts to a 38, and a 38.5-37.5 that convert to a 37, and a 37 - 35 that convert to a 36, etc. We also see when we do that how different the distributions really are from the old ones - they don’t track, as you had pointed out earlier. That’s a good reason to expect the new cut-offs NOT to be uniformly scaled down (by 12, or by .95, or by whatever people are arguing for).
But in reality, the conversion to last year doesn’t really matter right? What matters is who has the highest selection index using this year’s selection index, going down the list until the proportional allocations are met for each state?
The NMS will have more trouble at the cutoff because of the lack of granularity, but that may be it. Really, it doesn’t matter what last years cutoffs are, for this year.
Or am I missing something?
@suzyQ7 the tables are helpful in two ways: 1) translating this year’s score into a “last year percentile equivalent” so that you can compare to last year’s cut off and see whether you exceed or fall short; and/or 2) translating a last year’s score into a “this year’s percentile equivalent” so you can compare your current score to a previous score. That’s basically how I derived the cut-off for MN. Both concordances assume that the underlying population of students didn’t change all that much (while many more took the test this year and even the 11th grade population may be very different from prior years, I’m guessing at the top ranges that’s not as much, or even, the case). But they make no promises about whether the TEST this year resembles the test last year. Especially if different skills/knowledge are being tested. Therefore, the distributions can be very different, which is why the concordance tables are so helpful (even on a preliminary basis). If everything concorded uniformly, (i.e. scaled down by 12) then there would not be a need for a concordance table to convert scores.
I would tend to agree with you that the population for THIS year should determine this year’s cut-offs. But again, if the population is basically the same at the higher scores, you should be able to make some predictions even on a preliminary basis. Helpful for some to know whether they are “safe” either way or on the edge.
@GMTplus7- I saw the error too… Perfect score of 38 from 2015 only equates to a 79 of 2014… And it sb 80…
@suzyQ7- agreed! At the end of the day what matters is the top highest scores for each state is going to be NMSF. Everyone is anxious bc of the change in the scores. People at cc are high achievers so I wondered if people want to get a feel for things it’s better to get the kids & their friends to give their scores by STATE & create a table of those high scores. A big task lol!
@suzyQ7 Yes, conversion to last year is completely irrelevant. They can publish concordance tables every week, it won’t change the fact that the test is different from last year’s test and there’s no way to perfectly match 2015 PSAT scores to 2014 PSAT scores.
I lost which thread I was on… anyways
There are two different routes - Convergence Table and User Percentiles - to take on.
The two routes conflict with each other, so do not mix these two for any prediction/analysis.
Following the User Percentiles data route,
we established 1390 is the lowest USER 99%ile score.
Possible S.I. ranges for 1390 are 202 - 215 corresponding to very mathy (low-english) kid [760 math + 630 R+W] to [630 math + 760 R+W] perfect english kid.
Thus, the ** USER 99 percentile Selection Index must lie between 202 - 215. **
All the kids with 216 S.I. have 1400 or above PSAT scores (above 99%,) and all with 201 S.I. have 1380 or below (below 99%.)
Now, we line up the 1390 kids with their S.I. scores and have 98% or below kids stand-by.
Since S.I. has double weighting on R+W, for any potential 90%ile S.I. below 215, some very mathy kids get kicked out of 99% S.I. club to 98% or below, and perfect english kids with 1380 or below join the 99% club.
If 99%ile S.I. line goes down too low, e.g. 202, then the whole population of 1320 kids get to join 99% S.I. club and it swells to 97% PSAT score club so that’s too much. Going through this exercise, one can estimate
USER 99 percentile S.I. line must lie between ** 205 - 209. **
It needs to include all the kids with 99% R+W score (700) but cannot include majority of 1340 kids.
Soon someone will bring us new data. The 99 Percentile Selection Index from GC.
If that value lies outside of the above range, we will have three conflicting routes:
Convergence Table; PSAT score and subsection User Percentiles; S.I. Percentiles from GC
What A Joy!
@payn4ward I wish I paid more attention in Stats class 25 years ago.
I was doing the initial math and the 12 point sliding scale just doesn’t add up. I got a 1470 and a selection index of 221, with CR 38, W 36, and M 36.5. Going off the correlation tables, my 1470 is worth a 223 from last year. But using 221/228, I get 232.63/240. I have no clue how the ratio holds up given the different weight.
Additionally, NJ had 224 for its cutoff last year- is that now a straight 212? Am I okay with my 221(converted 233??) Am I even converting this right? The ratio seems to be between .95 and .97.
What
@payn4ward
Based on your calculations would I have a shot at merit. I am from, a generally uncompetitive state, and got a 1380, which is only 98th percentile user score, but thanks to my 730 in writing/reading, my si is 211. Could I still get merit even though I’m not in the 99th percentile nationally for my score out of 1520
FYI
Food for thought:
The easy & hard states to make NMSF
http://talk.collegeconfidential.com/sat-act-tests-test-preparation/1851217-the-easy-and-hard-states-for-making-nmsf.html#latest
@GMTplus7
So would a 211 be competitive in iowa, which is where I live? It would be above previous years cutoff of 208
@kyrielrving2 Yes. S.I. decides nm status and you are likely above 99% in S.I. It is quite close so you won’t know for sure until September but I think it’s likely you make it.
.
** Score multiplicity - There is room on the top **
=====================================================================
2015 S.I. with Possible # of wrong answer combination | | | Understanding 2014 Scores
S.I. | | # # | Loss | | #R | R | #W | W | #M | M | S.I. | | # | | Loss | | #R | R | #W | W | #M | M
228 | | 0,1, | 0.0 | | 0,1 | 38 | 0 | 38 | 0 | 38.0 | | | 240 | | 0, | 0.0 | | 0, | 40.0 | 0 | 40.0 | 0 | 40.0
228 | | 1,2, | 0.0 | | 0,1 | 38 | 0 | 38 | 1 | 38.0 | | | 240 | | 1, | 0.0 | | 1, | 40.0 | 0 | 40.0 | 0 | 40.0
227 | | 2,3, | 0.5 | | 0.1 | 38 | 0 | 38 | 2 | 37.5 | | | 238 | | 1,2 | 1.0 | | 0,1 | 40.0 | 1 | 39.0 | 0 | 40.0
227 | | 3,4, | 0.5 | | 0,1 | 38 | 0 | 38 | 3 | 37.5 | | | 237 | | 2, | 1.5 | | 2, | 38.5 | 0 | 40.0 | 0 | 40.0
226 | | 1,2, | 1.0 | | 0,1 | 38 | 1 | 37 | 0 | 38.0 | | | 236 | | 1,2 | 2.0 | | 0,1 | 40.0 | 0 | 40.0 | 1 | 38.0
226 | | 2,3, | 1.0 | | 0,1 | 38 | 1 | 37 | 1 | 38.0 | | | 235 | | 3, | 2.5 | | 2, | 38.5 | 1 | 39.0 | 0 | 40.0
226 | | 2,3, | 1.0 | | 2,3 | 37 | 0 | 38 | 0 | 38.0 | | | 234 | | 3, | 3.0 | | 3, | 37.0 | 0 | 40.0 | 0 | 40.0
226 | | 3,4, | 1.0 | | 2,3 | 37 | 0 | 38 | 1 | 38.0 | | | 234 | | 2,3 | 3.0 | | 0,1 | 40.0 | 1 | 39.0 | 1 | 38.0
226 | | 4,5, | 1.0 | | 0,1 | 38 | 0 | 38 | 4 | 37.0 | | | 233 | | 2,3 | 3.5 | | 0,1 | 40.0 | 2 | 36.5 | 0 | 40.0
226 | | 5,6, | 1.0 | | 0,1 | 38 | 0 | 38 | 5 | 37.0 | | | 233 | | 2,3 | 3.5 | | 0,1 | 40.0 | 0 | 40.0 | 2 | 36.5
225 | | 6,7, | 1.5 | | 0,1 | 38 | 0 | 38 | 6 | 36.5 | | | 233 | | 3, | 3.5 | | 2, | 38.5 | 0 | 40.0 | 1 | 38.0
225 | | 3,4, | 1.5 | | 0,1 | 38 | 1 | 37 | 2 | 37.5 | | | 232 | | 4, | 4.0 | | 4, | 36.0 | 0 | 40.0 | 0 | 40.0
225 | | 4,5, | 1.5 | | 0,1 | 38 | 1 | 37 | 3 | 37.5 | | | 232 | | 4, | 4.0 | | 3, | 37.0 | 1 | 39.0 | 0 | 40.0
225 | | 4,5, | 1.5 | | 2,3 | 37 | 0 | 38 | 2 | 37.5 | | | 231 | | 3,4 | 4.5 | | 0,1 | 40.0 | 1 | 39.0 | 2 | 36.5
225 | | 5,6, | 1.5 | | 2,3 | 37 | 0 | 38 | 3 | 37.5 | | | 231 | | 5, | 4.5 | | 3, | 38.5 | 1 | 39.0 | 1 | 38.0
224 | | 2,3, | 2.0 | | 0,1 | 38 | 2 | 36 | 0 | 38.0 | | | 230 | | 5, | 5.0 | | 5, | 35.0 | 0 | 40.0 | 0 | 40.0
224 | | 3,4, | 2.0 | | 0,1 | 38 | 2 | 36 | 1 | 38.0 | | | 230 | | 4, | 5.0 | | 2, | 38.5 | 2 | 36.5 | 0 | 40.0
224 | | 4,5, | 2.0 | | 4,5 | 36 | 0 | 38 | 0 | 38.0 | | | 230 | | 4, | 5.0 | | 2, | 38.5 | 0 | 40.0 | 2 | 36.5
224 | | 5,6, | 2.0 | | 4,5 | 36 | 0 | 38 | 1 | 38.0 | | | 230 | | 3,4 | 5.0 | | 0,1 | 40.0 | 3 | 35.0 | 0 | 40.0
224 | | 7,8, | 2.0 | | 0,1 | 38 | 0 | 38 | 7 | 36.0 | | | 229 | | 6,7 | 5.5 | | 0,1 | 40.0 | 0 | 40.0 | 3 | 34.5
224 | | 3,4, | 2.0 | | 2,3 | 37 | 1 | 37 | 0 | 38.0 | | | 228 | | 6, | 6.0 | | 6, | 34.0 | 0 | 40.0 | 0 | 40.0
224 | | 4,5, | 2.0 | | 2,3 | 37 | 1 | 37 | 1 | 38.0 | | | 228 | | 4,5 | 6.0 | | 0,1 | 40.0 | 4 | 34.0 | 0 | 40.0
224 | | 5,6, | 2.0 | | 0,1 | 38 | 1 | 37 | 4 | 37.0 | | | 228 | | 4,5 | 6.0 | | 0,1 | 40.0 | 0 | 40.0 | 4 | 34.0
224 | | 6,7, | 2.0 | | 0,1 | 38 | 1 | 37 | 5 | 37.0 | | | 228 | | 6, | 6.0 | | 5, | 35.0 | 1 | 39.0 | 0 | 40.0
224 | | 6,7, | 2.0 | | 2,3 | 37 | 0 | 38 | 4 | 37.0 | | | 228 | | 4, | 6.0 | | 3, | 36.0 | 0 | 40.0 | 1 | 38.0
224 | | 7,8, | 2.0 | | 2,3 | 37 | 0 | 38 | 5 | 37.0 | | | 228 | | 5, | 6.0 | | 2, | 38.5 | 1 | 39.0 | 2 | 36.5
223 | | 8,9, | 2.5 | | 0,1 | 38 | 0 | 38 | 8 | 35.5 | | | 227 | | 5, | 6.5 | | 2, | 38.5 | 3 | 35.0 | 0 | 40.0
223 | | 6,7, | 2.5 | | 4,5 | 36 | 0 | 38 | 2 | 37.5 | | | 227 | | 5,6 | 6.5 | | 0,1 | 40.0 | 0 | 40.0 | 5 | 33.5
223 | | 7,8, | 2.5 | | 4,5 | 36 | 0 | 38 | 3 | 37.5 | | | 227 | | 5, | 6.5 | | 3, | 37.0 | 2 | 36.5 | 0 | 40.0
223 | | 4,5, | 2.5 | | 0,1 | 38 | 2 | 36 | 2 | 37.5 | | | 227 | | 5, | 6.5 | | 3, | 37.0 | 0 | 40.0 | 2 | 36.5
223 | | 5,6, | 2.5 | | 0,1 | 38 | 2 | 36 | 3 | 37.5 | | | 226 | | 7, | 7.0 | | 6, | 34.0 | 1 | 39.0 | 0 | 40.0
223 | | 8,9, | 2.5 | | 2,3 | 37 | 1 | 37 | 2 | 37.5 | | | 226 | | 6, | 7.0 | | 5, | 35.0 | 0 | 40.0 | 1 | 38.0
223 | | 6,7, | 2.5 | | 2,3 | 37 | 1 | 37 | 3 | 37.5 | | | 226 | | 4,5 | 7.0 | | 0,1 | 40.0 | 3 | 35.0 | 1 | 38.0
222 | | 3,4, | 3.0 | | 0,1 | 38 | 3 | 35 | 0 | 38.0 | | | 226 | | 4,5 | 7.0 | | 0,1 | 40.0 | 2 | 36.5 | 2 | 36.5
222 | | 4,5, | 3.0 | | 0,1 | 38 | 3 | 35 | 1 | 38.0 | | | 226 | | 5,6 | 7.0 | | 0,1 | 40.0 | 1 | 39.0 | 4 | 34.0
222 | | 6,7, | 3.0 | | 6,7 | 35 | 0 | 38 | 0 | 38.0 | | | 226 | | 5, | 7.0 | | 2, | 38.5 | 2 | 36.5 | 1 | 38.0
222 | | 7,8, | 3.0 | | 6,7 | 35 | 0 | 38 | 1 | 38.0 | | | 225 | | 6, | 7.5 | | 2, | 38.5 | 0 | 40.0 | 4 | 34.0
222 | | 9,10, | 3.0 | | 0,1 | 38 | 0 | 38 | 9 | 35.0 | | | 225 | | 6, | 7.5 | | 2, | 38.5 | 4 | 34.0 | 0 | 40.0
222 | | 10,11 | 3.0 | | 4,5 | 36 | 1 | 37 | 0 | 38.0 | | | 225 | | 6, | 7.5 | | 4, | 36.0 | 2 | 36.5 | 0 | 40.0
222 | | 6,7, | 3.0 | | 4,5 | 36 | 1 | 37 | 1 | 38.0 | | | 225 | | 6, | 7.5 | | 4, | 36.0 | 0 | 40.0 | 2 | 36.5
222 | | 8,9, | 3.0 | | 4,5 | 36 | 0 | 38 | 4 | 37.0 | | | 225 | | 7, | 7.5 | | 7, | 32.5 | 0 | 40.0 | 0 | 40.0
222 | | 9,10, | 3.0 | | 4,5 | 36 | 0 | 38 | 5 | 37.0 | | | 225 | | 6,7 | 7.5 | | 0,1 | 40.0 | 5 | 32.5 | 0 | 40.0
222 | | 8,9, | 3.0 | | 0,1 | 38 | 1 | 37 | 7 | 36.0 | | | 225 | | 6,7 | 7.5 | | 0,1 | 40.0 | 0 | 40.0 | 6 | 32.5
222 | | 6,7, | 3.0 | | 2,3 | 37 | 1 | 37 | 4 | 37.0 | | | 224 | | 8, | 8.0 | | 8, | 32.0 | 0 | 40.0 | 0 | 40.0
222 | | 7,8, | 3.0 | | 2,3 | 37 | 1 | 37 | 5 | 37.0 | | | 224 | | 7, | 8.0 | | 6, | 34.0 | 0 | 40.0 | 1 | 38.0
221 | | 10,11 | 3.5 | | 0,1 | 38 | 0 | 38 | X | 34.5 | | | 224 | | 5,6 | 8.0 | | 0,1 | 40.0 | 4 | 34.0 | 1 | 38.0
221 | | 7,8, | 3.5 | | 4,5 | 36 | 1 | 37 | 2 | 37.5 | | | 224 | | 7, | 8.0 | | 5, | 35.0 | 1 | 39.0 | 1 | 38.0
221 | | 8,9, | 3.5 | | 4,5 | 36 | 1 | 37 | 3 | 37.5 | | | 223 | | 9, | 8.5 | | 9, | 31.5 | 0 | 40.0 | 0 | 40.0
221 | | 6,7, | 3.5 | | 2,3 | 37 | 2 | 36 | 2 | 37.5 | | | 223 | | 6,7 | 8.5 | | 0,1 | 40.0 | 6 | 31.5 | 0 | 40.0
221 | | 7,8, | 3.5 | | 2,3 | 37 | 2 | 36 | 3 | 37.5 | | | 223 | | 7, | 8.5 | | 2, | 38.5 | 1 | 39.0 | 4 | 34.0
221 | | 8,9, | 3.5 | | 0,1 | 38 | 2 | 36 | 6 | 36.5 | | | 223 | | 6, | 8.5 | | 2, | 38.5 | 2 | 36.5 | 2 | 36.5
221 | | 10,11 | 3.5 | | 4,5 | 36 | 0 | 38 | 6 | 36.5 | | | 223 | | 6, | 8.5 | | 2, | 38.5 | 3 | 35.0 | 1 | 38.0
221 | | 9,10, | 3.5 | | 2,3 | 37 | 1 | 37 | 6 | 36.5 | | | 223 | | 7, | 8.5 | | 5, | 35.0 | 2 | 36.5 | 0 | 40.0
221 | | 9,10, | 3.5 | | 0,1 | 38 | 1 | 37 | 8 | 35.5 | | | 223 | | 7, | 8.5 | | 5, | 35.0 | 0 | 40.0 | 2 | 36.5
221 | | 10,11 | 3.5 | | 2,3 | 37 | 0 | 38 | 8 | 35.5 | | | 223 | | 5,6 | 8.5 | | 0,1 | 40.0 | 3 | 35.0 | 2 | 36.5
220 | | 8,9, | 4.0 | | 8,9 | 34 | 0 | 38 | 0 | 38.0 | | | 223 | | 8, | 8.5 | | 7, | 32.5 | 1 | 39.0 | 0 | 40.0
220 | | 9,10, | 4.0 | | 8,9 | 34 | 0 | 38 | 1 | 38.0 | | | 223 | | 7,8 | 8.5 | | 0,1 | 40.0 | 1 | 39.0 | 6 | 32.5
220 | | 4,5, | 4.0 | | 0,1 | 38 | 4 | 34 | 0 | 38.0 | | | 223 | | 6, | 8.5 | | 3, | 37.0 | 0 | 40.0 | 3 | 34.5
** Score multiplicity - There is room on the top **
Above table shows the possible combinations of number of wrong answers for each S.I. value.
For example, one can get 228 by (R ; W ; M)=(0 ; 0 ; 0) with no wrong answers or (0,1 ; 0 ; 0,1) one wrong in each reading and math and no wrong answers in writing as first two lines show.
One can get 221 with (0,1 ; 0 ; X=10), 10 wrong math, 0 writing, 0 or 1 wrong in reading, etc.
There are 55 (lines) x 2 = 110 different ways of getting Selection Index between 221 - 228.
The total number of wrong answers ranges from 0 to 11. (you cannot have more than 3 writing questions wrong due to its curve on 10/14 to reach 221.)
Compared on the right side is 2014 PSAT.
There are 75 (a lot less than 110) ways of getting 2014 Selection Index between 223 - 240.
The total number of wrong answers ranges from 0 to 9 in that range.
Thus, a lot of students can land between 221 - 228.
N.B. 2014 subsection scores were divided by 2 so that it goes up to 40 rather than 80. Each missed question costs 1.25 point, i.e. ommitted was treated the same as wrong.
I’m confused. My D3 scored a 220 with a (2; 2; 4). Where is that combination on the table?
@Mamelot I stopped at 221. 220 is shown just 2 lines but has much more combinations. I got tired and CC doesn’t allow posting more lines in one post 