Data preprocessing
Many factors affect the success of Machine Learning
(ML) on a given task. The representation and quality of the instance
data is first and foremost (Pyle, 1999). If there is much irrelevant and redundant
information present or noisy and unreliable data, then knowledge
discovery during the training phase is more difficult. It is well known
that data preparation and filtering steps take considerable amount of
processing time in ML problems. Data pre-processing includes data
cleaning, normalization, transformation, feature extraction and
selection, etc. The product of data pre-processing is the final training
set. It would be nice if a single sequence of data pre-processing
algorithms had the best performance for each data set but this is not
happened. Kotsiantis et al. (2006) present the most well know algorithms for each
step of data pre-processing so that one achieves the best performance
for their data set.
References
S. Kotsiantis, D. Kanellopoulos, P. Pintelas, Data Preprocessing for Supervised Leaning, International Journal of Computer Science, 2006, Vol 1 N. 2, pp 111-117.
Pyle, D., 1999. Data Preparation for Data Mining. Morgan Kaufmann
Publishers, Los Altos, CA.