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Comment by romaaeterna

4 hours ago

Coincidence? Of course not.

1998? I wanted a quarter century of Grade 8 and that gives me 1998 to 2024 with NAEP. 2000 reading assessment was Grade 4 only. You can do it with any pair of years.

The article says that scores began drifting down around 2012. Gemini is telling me that NAEP peaked in 2013. Elsewhere in this thread there's a claim of an inflection point around 2018 in PISA, which eyeballing Gemini's numbers lines up with NAEP.

Does this correlate with the racial proportion data?

  • If you graph actual NAEP since 1998 versus a 1998 group-fixed score, you'll see increases (1998-2002, 2005-2013, 2015-2017) and multiple declines twice taking the line back down to the 1998 linear trend prediction (2002-2005, 2017-2024).

    It is wrong to get overly exact here though. We are talking about a overall score variance of just 10pts in the face of an achievement gap of nearly 30pts, with an absolutely massive 20% decline in white population share over the 26 year period.

    • If you're seeing trends in your residuals that's a sign of a violation of the independence assumption of linear models.

      I'm in a different field but arbitrary 27 years (1998-2024) of data and the autocorrelation both would get flagged in a review for me. Not to give statistics homework but you should test and correct the autocorrelation issue you're describing in the model. It's probably underspecified in some way (e.g. correcting for income or other demographics).