Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fast k-means algorithm clustering   k-means has recently been recognized as one of the best algorithms for
clustering unsupervised data. Since k-means depends mainly on distance
calculation between all data points and the centers, the time cost will be high
when the size of the dataset is large (for example more than 500millions of
points). We propose a two stage algorithm to reduce the time cost of distance
calculation for huge datasets. The first stage is a fast distance calculation
using only a small portion of the data to produce the best possible location of
the centers. The second stage is a slow distance calculation in which the
initial centers used are taken from the first stage. The fast and slow stages
represent the speed of the movement of the centers. In the slow stage, the
whole dataset can be used to get the exact location of the centers. The time
cost of the distance calculation for the fast stage is very low due to the
small size of the training data chosen. The time cost of the distance
calculation for the slow stage is also minimized due to small number of
iterations. Different initial locations of the clusters have been used during
the test of the proposed algorithms. For large datasets, experiments show that
the 2-stage clustering method achieves better speed-up (1-9 times).

16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin