<p>Some more stats to help the discussion.</p>
<p>There are ~4 million seniors in the country, and ~1.5 million took the PSAT test last October – 38% of all seniors took the test.</p>
<p>There are ~41,000 high schools in the country, and students from ~22,000 high schools took the test – 54% of all high schools “participated”.</p>
<p>I believe the sample space is of sufficient size to generate meaningful discussion on aggregates and overall implications.</p>
<p>Based on 22,000 participating high schools and only 16,000 NMSF’s, the average number of NMSF’s per participating school is less than 1. If we have an even distribution of NMSF’s among the schools and ignore differences in school size, then 30% percent of the school will not have any NMSF. Once we factor in the school size difference and the possibility of large student population concentrated in small fraction of the schools, that 30% will increase, but based on the data I was able to gather, this factor alone does not bring the percentage of schools without NMSF to anywhere close to 80% of the participating schools.</p>
<p>Btw, the fact that NMSF is determined per state specific cutoff’s actually made the stats look better, not worse, because the number of NMSF’s allocated to each state is fixed based on the total number of seniors in that state, and not based on the number of PSAT takers in that state. This explains why in some ACT dominated states, the percentage of PSAT takers who made the NMSF cutoff is much higher than other states. It made the stats better because a smaller fraction of the schools are participating and this raises the percentage of participating schools with NMSF’s in that state. I’ll give an extreme example to illustrate this point. If only 2 schools out of 100 are participating, and the state is allocated with 10 NMSF’s, then as long as each of the two participating schools gets at least one NMSF, the state can claim 100% success for its participating schools. </p>
<p>I thank folks for providing various reasons to explain this phenomenon. After sleeping on this one last night, I’m not as surprised as I was yesterday. I still think the gap between 30% and 80% is huge and cannot be explained easily by any one factor. </p>
<p>I am curious of what people think is the single biggest factor contributing to this gap?</p>