Possible corresponding range of NM Selection Indices vs. 2015 PSAT scores

Test Preparation
1

I have crunched the different possible combinations of PSAT sub-scores and determined that these are the possible ranges of 2015 PSAT scores vs. corresponding NM Selection Index ranges.

Since PSAT score and NMSF Selection Index are computed using different formulas, there is not a one-to-one correspondence between the 2 numbers. The PSAT score calculation gives twice as much weighting to the M sub-score:

PSAT = 10 * ((2*M) + V + CR)
NM S.I. = 2 * (M + V + CR)

PSAT | NMSF Selection Index range

1200 | 176 - 184
1210 | 178 - 186
1220 | 178 - 188
1230 | 180 - 190
1240 | 180 - 192
1250 | 182 - 194
1260 | 182 - 196
1270 | 184 - 198
1280 | 184 - 200
1290 | 186 - 202
1300 | 186 - 204
1310 | 188 - 206
1320 | 188 - 208
1330 | 190 - 208
1340 | 192 - 210
1350 | 194 - 210
1360 | 196 - 212
1370 | 198 - 212
1380 | 200 - 214
1390 | 202 - 214
1400 | 204 - 216
1410 | 206 - 216
1420 | 208 - 218
1430 | 210 - 218
1440 | 212 - 220
1450 | 214 - 220
1460 | 216 - 222
1470 | 218 - 222
1480 | 220 - 224
1490 | 222 - 224
1500 | 224 - 226
1510 | 226

1520 | 228

S.I. | PSAT score range

190 | 1230 - 1330
192 | 1240 - 1340
194 | 1250 - 1350
196 | 1260 - 1360
198 | 1270 - 1370
200 | 1280 - 1380
202 | 1290 - 1390
204 | 1300 - 1400
206 | 1310 - 1410
208 | 1320 - 1420
210 | 1340 - 1430
212 | 1360 - 1440
214 | 1380 - 1450
216 | 1400 - 1460
218 | 1420 - 1470
220 | 1440 - 1480
222 | 1460 - 1490
224 | 1480 - 1500
226 | 1500 - 1510
228 | 1520

2

Thanks, indeed these are interesting set of numbers this year.

Not nitpicking or anything but odd number SIs are possible as they are giving sub scores in 0.5’s, such as 37.5 thus odd number SIs such as 203, 211 are possible.

3

I know indeed that odd SI’s are possible. S2 has an odd one.

But my spreadsheet was getting ungainly, so I “kept it simple”. :wink:

4

I feel like the new test doesn’t discriminate between high scores as well as the old one. This is anecdotal, but 6 people at my school got a 225-226. Haven’t heard of any 228s yet. On the old PSAT few people got 238, 239, 240. A much higher occurrence of the max score could cause the national merit cutoffs to be very close to what they were last year.

5

FYI, My calculations in post#1 plotted in a table alongside the College Board’s PRELIM concordance table:

http://talk.collegeconfidential.com/discussion/comment/19169349/#Comment_19169349

6

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