Preprocess: u'geoNetwork.city', u'geoNetwork.cityId', u'geoNetwork.continent',

[wesleytian]

Preprocess the following features:

u'geoNetwork.city',
u'geoNetwork.cityId',
u'geoNetwork.continent',

1. Standardization: http://scikit-learn.org/stable/modules/preprocessing.html#standardization-or-mean-removal-and-variance-scaling

2. Impute missing values: http://scikit-learn.org/stable/modules/impute.html

3. Normalization: http://scikit-learn.org/stable/modules/preprocessing.html#normalization

4. Encode categorical features (optional): http://scikit-learn.org/stable/modules/preprocessing.html#encoding-categorical-features

5. Discretization (optional): http://scikit-learn.org/stable/modules/preprocessing.html#discretization

http://scikit-learn.org/stable/modules/preprocessing.html

[htcao]

It seems that the values of feature geoNetwork.cityId in the dataset are all missing, how to deal with that?