Homework 1: pdf , Code and Data,    Tex Source,    Solutions.
Homework 1 Corrections and Clarifications:
- While this correction pertains to an already completed homework, it is important to note there was an error in question 2.4. - the alternative splitting method. The question stated that if you minimized the equation for O(a,t) with respect to a and t, you would find the optimal split for the misclassification rate criteria. However, this function was missing something important. The terms summing the number of samples misclassified above and below the split point should have been normalized. Specifically, the term summing the number of samples misclassified above the split should have been divided by the total number of samples above the split and the term summing the number of samples misclassified below the split should have been divided by the total number of samples below the split.
Homework 2: pdf ,    Data,    Tex Source,    Solutions.
Homework 2 Corrections and Clarifications:
- The original homework assignment stated there was a third optional question. This was incorrect. There are only two required (and no optional) questions.
- When using the MAP estimate for question 2.5, note that hallucinating each word appearing Beta times in the training set corresponds to having a Dirichlet prior with all parameters equal to (Beta + 1). Ensure that you are not adding (Beta - 1) to your word counts, since that may result in negative probabilities. Also, we are hallucinating each word appearing Beta times in the entirety of the training set, not Beta times per document.
Homework 3: pdf ,    Tex Source,    Solutions.
Homework 3 Corrections and Clarifications:
- Question 3.1(a) The joint distribution on the left of the equation in 3.1(a) should be P(A,B,C,D,E,F,G) and not P(A,B,C,D,E,F).
- Question 2(d): Please replace the current hint by this hint: "Your expression can involve integrals, and if it does you need not solve them. However, there is a much simpler answer that does not involve integrals so look for that!"
Homework 4: pdf ,    Tex Source,    Solutions.
Homework 5: pdf ,    Tex Source,    Solutions.
Homework 5 Corrections and Clarifications:
- Question 3.1 This question incorrectly sometimes indexed the vector x by t. However, these vectors should have been indexed by i. The homework file has been updated
Homework 6: pdf ,    Tex Source,    Solutions.
Так, значит, вы не по поводу моей колонки. - Нет, сэр. Казалось, старик испытал сильнейшее разочарование. Он медленно откинулся на гору подушек.