16. The system of claim 2 , wherein the first not fully specified data record does include a second numeric data value for the second variable in the plurality of variables and does not include a third numeric data value for a third variable in the plurality of variables, and wherein the obtaining comprises obtaining, using the generated representation and an optimization technique, the first numeric data value and the third numeric data value based on the second numeric data value.
2. A system, comprising: using at least one hardware processor to perform: accessing input data comprising: training data comprising a first plurality of data records, each of the first plurality of data records having numeric data values at least for first and second variables in a plurality of variables; and a second plurality of data records comprising at least a first not fully specified data record that does not include a first numeric data value for the first variable in the plurality of variables; generating, using the training data, a representation of a relationship between the first variable and at least the second variable in the plurality of variables; and obtaining, by the computer system and using the generated representation, at least the first numeric data value for the first variable in the first not fully specified data record.