The following LaTeX code creates a redundant and unwanted arrow head in the Measures block.
\documentclass[border=10pt]{standalone}
\usepackage{tikz}
\usetikzlibrary{arrows,positioning,shapes.geometric}
\begin{document}
\begin{tikzpicture}[>=latex']
\tikzset{block/.style= {draw,rectangle,align=center,minimum width=2cm,minimum height=1cm}}
\node [block] (measures) {Measures};
\node [block, above right =2cm of measures](accuracy) {Accuracy};
\node [block, below =0.5cm of accuracy] (precision) {Precision};
\node [block, below =0.5cm of precision] (recall) {Recall};
\node [block, below =0.5cm of recall] (fmeasure) {Fmeasure};
\path[draw,->]
(measures.east) edge (accuracy.west)
(measures.east) edge (precision.west)
(measures.east) edge (recall.west)
(measures.east) edge (fmeasure.west)
;
\end{tikzpicture}
\end{document}
The code produces following image.
Is there a way to get rid of that?