D.3 Lesson updates are complete

I’ve just uploaded the last new video for lesson D.3.4, and with that, the updated D.3 lessons are complete.

D.3 has undergone the most significant changes of the D.1-D.3 set.

First, the old D.3.4 lesson on estimating GLM models moved (with a major overhaul as well) to the new D.2.3 lesson.

Second, I elected to remove the discussion of the score statistic from the old D.3.1 lesson.  This is a topic that is not covered in a clear way in our source text, and the examiners for MAS-I and Exam S before that seem not to have any interest in the topic – with good reason, I think since I don’t think anyone actually uses the Score statistic for model testing.  The Score is useful for the GLM estimation procedure in D.2.3, and it is only in that context that we have seen it appear on the exam, so that’s where problems relating to the score will be found for the updated lessons.

The next change concerns Prediction intervals.  The old lesson D.3.5 included formulas for Prediction intervals in the multivariable normal and the single variable regression case, even though these formulas do not appear in our source texts.   Since the formulas have not been needed since the change from Exam S to MAS-I, I am now confident that these formulas are no longer required.  They do appear in the discussion of prediction intervals in the new lesson D.3.1, but without the need for computational examples, the overall content of the old D.3.2 and D.3.5 has now been combined into a single lesson.

Finally, I’ve significantly simplified the presentation from the old D.3.6 and D.3.7 lessons into the new D.3.3 and D.3.4 lessons.

I’m very pleased with how all of the new lessons have come out.  I believe that these new lessons are more clear and more focused on the aspects of the syllabus content that are of the most interest to our exam writers.

While the lesson updates to B.4, D.1, D.2, and D.3 all complete, there are many auxiliary items that need attention.   So for the next bit, I’ll be working on the lesson problems, summary sheets, flashcards, and review lessons for these sections of new lessons.