Weighted Nearest Neighbour Imputation.
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#include <yat/utility/WeNNI.h>

std::vector< std::pair< size_t, double > >  calculate_distances (const size_t) const 

std::vector< size_t >  nearest_neighbours (const size_t, const std::vector< std::pair< size_t, double > > &) const 

Weighted Nearest Neighbour Imputation.
WeNNI is a continuous weights generalization of the (binary weights) kNNI algorithm presented by Troyanskaya et al. A reference to this paper is found in the NNI document referred to in the NNI class documentation. The NNI document also describes WeNNI in depth.
 Note
 Missing values should be represented with a zero weight. WeNNI will treat the corresponding data values as zero, i.e., this implies that NaNs and Infs with zero weight will not have any impact on calculations.a
 See also
 NNI and kNNI
std::vector<std::pair<size_t,double> > theplu::yat::utility::NNI::calculate_distances 
( 
const size_t 
 ) 
const 

protectedinherited 
where C is the number of columns
unsigned int theplu::yat::utility::WeNNI::estimate 
( 
void 
 ) 


virtual 
Function doing WeNNI imputation.
Perform WeNNI on data in matrix with continuous uncertainty weights in weight using neighbours for the new impute value.
The return value can be used as an indication of how well the imputation worked. The return value should be zero if proper preprocessing of data is done. An example of bad data is a matrix with a column of zero weights, another is a corresponding situation with a row with all weights zero.
 Returns
 The number of rows that have at least one value not imputed.
Implements theplu::yat::utility::NNI.
const utility::Matrix& theplu::yat::utility::NNI::imputed_data 
( 
void 
 ) 
const 

inherited 
 Returns
 A const reference to the modified data.
const utility::Matrix& theplu::yat::utility::WeNNI::imputed_data_raw 
( 
void 
 ) 
const 
 Returns
 A const reference to imputed_data_raw.
std::vector<size_t> theplu::yat::utility::NNI::nearest_neighbours 
( 
const size_t 
, 


const std::vector< std::pair< size_t, double > > & 


) 
 const 

protectedinherited 
Contributing nearest neighbours are added up to the user set number, and neighbours are disqualified if their element (column) weight is zero
const std::vector<size_t>& theplu::yat::utility::NNI::not_imputed 
( 
void 
 ) 
const 

inherited 
 Returns
 indices of rows in data matrix not imputed
unsigned int theplu::yat::utility::NNI::neighbours_ 

protectedinherited 
number of neighbor to use
std::vector<size_t> theplu::yat::utility::NNI::not_imputed_ 

protectedinherited 
which rows are not imputed due to lack of data
The documentation for this class was generated from the following file: