Robust L-Isomap with a Novel Landmark Selection Method

Figure 5

Edge density of each edge in the neighbourhood graph for the case of Swiss roll data. The number of the data points is 1000. (a) The -nearest neighbourhood graph with . (b) The edge density values are well-distributed for the case of . (c) The -nearest neighbourhood graph with . There are some short-circuit edges in this case. (d) The orange line denotes the threshold . Some edges have extremely low edge density values that are considered as short-circuit edges.

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