CS281A/Stat241A Homework Assignment 1 (due September 14, 2015)
1. (Directed graphical models and conditional probabilities)
A standard test for prostate cancer, the prostate specic antigen (PSA) test, has a sensitivity of around
95% and a specicity of aro
CS281A/Stat241A Homework Assignment 2 (due October 1, 2015)
1. (Phylogenetic tree inference)
In this problem, you will implement sum-product algorithm for an undirected graph that one
frequently sees in population genetics: a phylogenetic tree.
In such a
CS281A/Stat241A Homework Assignment 3 (due October 15, 2015)
1. (Multiclass Classication)
Suppose that we wish to model an unordered discrete response variable Y (such as which folder should
be suggested as the destination for a document), conditioned on
CS281A/Stat241A Homework Assignment 4 (due October 29, 2015)
1. (K-means) Show that the K-means algorithm,
j
zi := 1 j = arg min xi k
k
j :=
j
i zi xi
j
i zi
performs coordinate descent in the cost function
n
K
j
zi xi j
J(z, ) =
2
,
i=1 j=1
1
K
where the
Undirected Graphical Models:
Chordal Graphs, Decomposable Graphs,
Junction Trees, and Factorizations
Peter Bartlett. October 2003.
These notes present some properties of chordal graphs, a set of undirected graphs
that are important for undirected graphica