deletions | additions       diff --git a/section_begin_itemize_item_Err__.tex b/section_begin_itemize_item_Err__.tex  index 4f5a677..3ed5ed9 100644  --- a/section_begin_itemize_item_Err__.tex  +++ b/section_begin_itemize_item_Err__.tex 
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0 & j_1 < j_2 \\   1 & j_1 > j_2  \end{matrix}\right.\\  Err_{\{X\},\{Y\}} Err(X,Y)  = \sum_{\substack{v\neq w\\ v,w\epsilon \{X\},\{Y\}}}Err_{v,w}  $$  \end{definition}