CAS Exam Errata
We always hated seeing errors in study material when taking exams, so we check everything as much as possible. If you do see a mistake, check out the up-to-date errata below for any corrections.
Accidents Happen ...
If you spot an error in the study material, please send us a message so that we can correct the error and document it here for others.
Errata by Exam
No errata has yet been found for the Fall 2025 sitting.
No errata has yet been found for the Fall 2025 sitting.
No errata has yet been found for the Fall 2025 sitting.
No errata has yet been found for the Fall 2025 sitting.
Study Guide & Review Videos
Clark (1/5/25) – On page 20, the third bullet should say “R/IV = 57%” instead of “(R+L)/IV = 57%.”
Mildenhall Ch. 4 (2/4/25) – On page 108, it should say “If p = 1 – 1/n,” rather than “Since F(x) = p = 1 – 1/n.” The “p” here incorporates frequency and severity, not just severity. The video will be updated as well.
Mildenhall Ch. 4 (2/12/25) – In the Ch. 4 video, when the n-year occurrence PML is defined, it still says “at least 1/n.” This will be revised to “at most 1/n” to align with the study guide (this is incorrect in the textbook).
Brehm Ch. 2 (2/26/25) – On page 286, in the second to last bullet, economic margin is incorrectly described as the return above the cost of capital. It should just refer to economic margin as the “profit margin.”
Panning (3/3/25) – On page 263, under the “Advantage,” it should say “seek to reduce the duration of the firm’s total economic value by…”
Mildenhall Ch. 5 (3/17/25) – On page 127, the bid-ask spread should be defined as rho(X) – (–rho(-X)). Then, in the example below the definition, the final spread should be rho(H) – (-rho(-H)) = rho(H) – (-rho(C-1)) = rho(H) + rho(C) – 1 = 0.316 + 0.95 – 1 = 0.266 > 0. The definition of the bid-ask spread will be corrected in the video as well.
Brehm Ch. 2 (3/24/25) – On page 282, the marginal decomposition of the exponential moment has a typo. The “r'(X_j)” should be replaced with E[X_j * e^(cY/E[Y])]. This will be corrected in the video as well.
Cookbook
Mildenhall Pt 2 – Classical PCPs (2/9/25) – The PDF version shows a typo in the semivariance formula. The squared should be outside the parenthesis instead of inside squaring E(X):
E( (X-E(X))^2 where X>= E(X) )
Practice Problems
RF Bernegger – 2 (11/25/24) – The data in the table didn’t exactly sum to a 100% probability. We fixed this.
High-Level Summaries
Mildenhall 14-15 (4/7/25) –
The unit premium formula using risk adjusted expected proportion of recoveries has a typo. At the end of the formula should be g(S) but it just has S. It has been fixed.
Clark (12/20/24) – On page 3 of the Clark summary, the ELF formula has a ‘U’ in the numerator instead of an ‘L’. It has been fixed.
Flashcards
Mildenhall Ch. 8 (1/22/25) – On page 24 of the standard PDF, the fifth reason should say “…technically insolvent…”
Clark (12/16/24) – On page 48 of the standard PDF, there was an “U” in the subscript of the ELF that should not have been there. It has been removed.
Panning (3/3/25) – On page 26 of the standard PDF, under the “Advantage,” it should say “seek to reduce the duration of the firm’s total economic value by…”