Feature Selection

Ecological data sets are often high dimensional: data sets derived from satellite imagery may contain hundreds of intercorrelated spectral bands. It is desirable to train from a reduced set of attributes, to reduce both the size of the model-fitting search space, and the risk of over-fitting the data.

There are two common approaches: filters and wrappers. Filter methods pre-analyze the data to select a suitable subset of the available features - for example, principal component analysis may be used to generate and select a small number ofhighly influential features for training. However, the model-learning phase may uncover higher-order interactions which are invisible to a filter approach; these are better handled by wrapper approaches, which 'wrap' an optimization algorithm around the underlying model-learning algorithm, repeatedly training from different feature sets until a good feature set is found. Evolutionary algorithms are frequently used as the wrapper.

Was this article helpful?

0 0
10 Ways To Fight Off Cancer

10 Ways To Fight Off Cancer

Learning About 10 Ways Fight Off Cancer Can Have Amazing Benefits For Your Life The Best Tips On How To Keep This Killer At Bay Discovering that you or a loved one has cancer can be utterly terrifying. All the same, once you comprehend the causes of cancer and learn how to reverse those causes, you or your loved one may have more than a fighting chance of beating out cancer.

Get My Free Ebook

Post a comment