similarity.threshold: Lower bound on string-distance measure for being considered a possible match. If an observation has no possible matches above this threshold, it is discarded from the match. Default is 0.8.
stringdist.method: The method to use for calculating string-distance similarity. Possible values are 'jaro' (Jaro Distance), 'jw' (Jaro-Winkler), and 'lv' (Levenshtein). Default is 'jw'.
jw.weight: Parameter that describes the importance of the first characters of a string (only needed if stringdist.method = "jw"). Default is .10.
n.cores: Number of cores to parallelize over. Default is NULL.
Returns
A list of length two, where the both entries are a vector of indices to be included in the match from dataset A (entry 1) and dataset B (entry 2).