Methods, devices and systems for data augmentation to improve fraud detection
A computer-implemented method of generating an augmented electronic text document comprises establishing a directed multigraph where each vertex is associated with a separate language and is connected to at least one other one of the vertices by an oriented edge indicative of a machine translation engine's ability to translate between languages associated with the vertices connected by the oriented edge with acceptable performance. The directed multigraph is then traversed starting at a predetermined origin vertex associated with an original language of the original electronic text document by randomly selecting an adjacent vertex pointed to by an oriented edge connected to the predetermined origin vertex and causing a machine translation engine to translate the original electronic text document from the original language to a language associated with the selected vertex. The directed multigraph is then further traversed as allowed by the oriented edges from the intermediate vertex to successive other next-adjacent connected vertices, each time machine translating a previously-translated electronic text document into a language associated with a randomly-selected next-adjacent vertex until the predetermined origin vertex is selected and the previously translated electronic text document is re-translated into the original language and designated as the augmented electronic text document.
1. A computer-implemented method, comprising:
providing and storing an electronic text document in a memory of a computer and generating an augmented electronic text document from the provided electronic text document by successively transforming the electronic text document by iteratively:
selecting an element in the provided electronic text document;
generating a list comprising a plurality of potential replacement elements from a source of potential replacement elements of a type of the selected element;
calculating a value of each of the plurality of potential replacement elements in the generated list using a predetermined metric;
ranking the values of the plurality of potential replacement elements in the generated list in decreasing order of the calculated value;
randomly selecting an index into the ranked list according to a predetermined probability distribution, an index associated with a higher-ranked potential replacement element of the plurality of potential replacements being more likely to be selected than an index associated with a comparatively lower-ranked potential replacement element of the plurality of potential replacements; and
replacing the selected element in the provided electronic text document with the potential replacement element at the randomly-selected index.
2. The computer-implemented method of claim 1 , wherein the probability distribution is a one of a geometric, uniform, Gaussian and Poisson probability distribution.