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$\displaystyle P(w_{i}\vert w_{i-1}^{i-2}) =\left\{ \begin{array}{ll}
\lambda(w_...
... \ N(w_{n-2}^{n-1}) \\
P(w_{i}\vert w_{i-1}) & other \\
\end{array} \right.$     (2.24)

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2019-03-29