Merge pull request #104 from KarahanS/master

fix doc for edge histogram

doc/kernels/edge_histogram.rst

@@ -6,7 +6,7 @@ Edge Histogram Kernel
 The edge histogram kernel is a basic linear kernel on edge label histograms.
 The kernel assumes edge-labeled graphs.
 Let :math:`\mathcal{G}` be a collection of graphs, and assume that each of their edges comes from an abstract edge space :math:`\mathcal{E}`.
-Given a set of node labels :math:`\mathcal{L}`, :math:`\ell : \mathcal{E} \rightarrow \mathcal{L}` is a function that assigns labels to the edges of the graphs.
+Given a set of edge labels :math:`\mathcal{L}`, :math:`\ell : \mathcal{E} \rightarrow \mathcal{L}` is a function that assigns labels to the edges of the graphs.
 Assume that there are :math:`d` labels in total, that is :math:`d = |\mathcal{L}|`.
 Then, the edge label histogram of a graph :math:`G=(V,E)` is a vector :math:`\mathbf{f} = (f_1, f_2, \ldots, f_d)`, such that :math:`f_i = |\{ (v,u) \in E : \ell(v,u) = i \}|` for each :math:`i \in \mathcal{L}`.
 Let :math:`\mathbf{f}, \mathbf{f}'` be the edge label histograms of two graphs :math:`G, G'`, respectively.