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#102




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#103




I think it is a firsttime user discount. When I go on the website without being logged in, most of the courses are showing as around $200 with a slash through it, and the price reduced to $11.39
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#105




Ridge regression vs. lasso
I am having hard time understanding the one important difference between ridge regression and lasso:
the lasso has the effect of forcing the coefficient estimates to be exactly zero, however, for ridge regression the coefficient estimates are reduced but none are reduced to exactly zero (taken from the ACTEX Manual) why is this? I understand both would be nonnegative since one is sum of squared X's and one is sum of absolute values, but why can't the sum of squared X's be zero? Thanks! 
#106




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The fact that the lasso can make the coefficient estimates exactly zero when lambda is sufficiently large relies mostly on a mathematical argument which is not very important for Exam PA. It has to do with the geometry of the contours of the penalty function. If you are interested, please read pages 221222 of Introduction to Statistical Learning.
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Ambrose Lo, PhD, FSA, CERA Associate Professor of Actuarial Science (with tenure) Department of Statistics and Actuarial Science The University of Iowa ACTEX Manual for SOA Exam PA  ACTEX Manual for SOA Exam SRM  ACTEX Manual for CAS Exam MASI Textbook: Derivative Pricing: A ProblemBased Primer (useful for derivatives portion of Exam IFM) 
#107




I'm already a bit decent with R so some of this stuff isn't a problem. Completed all the modules + exercises too. I'm also looking at the exam SRM sample questions...?
I'm just not sure how to prepare for this kind of fivehour thing. I've downloaded all the practice projects and past exams, so would giving them in examesque conditions on weekends, say every Saturday, help out? What else is there?
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#108




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Is it available now? I gonna take education, but it seems to be unvalid Sent from my iPhone using Tapatalk 
#109




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Hoping that this + ISLR + modules + old exams will be enough... has anyone heard about the manual's release? I'm working through everything else, but would feel a lot better if that was out.
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#110




I've posted this elsewhere, and at the risk of making it the mean grade go higher, making it harder to pass ... read this CAS monograph on GLMs
https://www.casact.org/pubs/monograp...hareTevet.pdf It is super helpful and written for practical use. It should be included in the exam materials IMO, that is how relevant it is (mostly Chapters 2, 3, 4, 5, 6.1, 7.3). I should have read it before taking and failing the last exam! 
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