<p>I think the errors that are possible are that the scores for composite and math might be too low, and scores for critical reading and writing too high.</p>

<p>No, the composite scores are way too high. Just because 99th percentile is 760 in all three sections doesn't mean 2280 is the mininum 99th percentile. Not all 760 Math people score 760 in all of the other sections. This is what makes 99th percentile in all three sections unique. A 99th percentile on the New SAT is like a 2170-2180. How do I know? 1470-1480 was 99th percentile on the old SAT and 2170-2180 is about equivalent to that. Its a longer test, you know, mor fatigue, more sections, lower scores.</p>

<p>From the data I've collected, it seems that even on CC, the writing distribution is higher in general by 10-20 points over the math and critical reading distributions.</p>

<p>While top 800 scores may decrease, 700+ scores should be of greater frequency in this section compared to the frequency of those in math and critical reading.</p>

<p>I should have made myself clear on that statement. That was based on data collected from CC and compared to math and critical reading data collected from CC. I understand it's a small sample and hardly representative of the population, a paired difference of means helps to filter out the fact it is not representative of the population.</p>

<p>What data did you use? I collected about 50-55 results from kids who took the June SAT & it was consistent w/ the data I had from the March SAT: Math was 15 points higher than reading. Reading was 10 points higher than writing.</p>

<p>And also, 1470 on the old SAT was 99th percentile. With writing being the toughest section, 99th percentile will be below 2200 (but not much).</p>