1. A computer-implemented method for product classification, the method comprising: receiving, by one or more processors of a server, a product record associated with a product, the product record comprising a description of the product; generating, by the one or more processors, a first ranked list of product types based on the product record using a plurality of rule-based classifiers; generating, by the one or more processors, a second ranked list of product types based on the product record using a plurality of machine learning-based classifiers; aggregating, by the one or more processors, the first ranked list of product types and the second ranked list of product types to generate a combined ranked list of product types; providing the description of the product and a portion of the combined ranked list of product types to a crowdsourcing computer network for evaluation; and returning, from the crowdsourcing computer network, a validation decision, wherein: when the crowdsourcing computer network determines that a type of the product is correct, the validation decision indicates that the type of the product is correct; when the crowdsourcing computer network determines that the type of the product is not correct, the validation decision indicates that the type of the product is not correct; and when the crowdsourcing computer network determines that the description of the product is insufficient to accurately judge whether the type of the product is correct, the validation decision indicates that the type of the product is unclear.