Recall from Chapter 2.1 that a linear threshold function (abbreviated LTF) is a boolean-valued function $f : \{-1,1\}^n \to \{-1,1\}$ that can be represented as \begin{equation} \label{eqn:generic-LTF} f(x) = \mathrm{sgn}(a_0 + a_1 x_1 + \cdots + a_n x_n) \end{equation} for some constants $a_0, a_1, \dots, a_n \in {\mathbb R}$.

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Ohad Klein: In lemma 46 (48) - should it be $i \not \in J'_x$? (In its ...Ohad Klein: Another one - is the symbol "union" is redundant in 37b,c?Ohad Klein: I might be misunderstanding 37b. Suppose k=n=1. Then $E[f^q]...Ohad Klein: I might be wrong, but in ex. 9.31 (i.e. remark 9.29), I trie...Ohad Klein: sorry, my bad, again!Ohad Klein: In 23, is it $q \leq 2+2\epsilon$?Ohad Klein: ctrl+f: Paresval.