1. A computer-implemented system comprising: one or more computers; one or more data storage devices coupled to the one or more computers, storing: a predictive model repository of a plurality of trained predictive models, information that describes each of the trained predictive models, which information includes an indication for each trained predictive model of one or more input types of input data that are compatible with the trained predictive model and an output type of a predictive output that can be generated using the trained predictive model, and instructions that, when executed by the one or more computers, cause the one or more computers to perform operations comprising: receiving a request from a client-subscriber computing system for access to a trained predictive model from the predictive model repository, which trained predictive model can generate a predictive output in response to receiving input data having one or more input types, wherein the one or more input types can be determined from the request; determining from the information that describes each of the trained predictive models that one or more models included in the predictive model repository match the request from the client-subscriber computing system, wherein determining a match is based at least in part on a comparison of the one or more input types determined from the request to input types included in the information that describes the trained predictive models; and providing access to at least one of the one or more models to the client-subscriber computing system; wherein the one or more models that match the request are models that were trained using training data provided by a computing system other than the client-subscriber computing system.
1. A computer-implemented system comprising: one or more computers; one or more data storage devices coupled to the one or more computers, storing: a predictive model repository of a plurality of trained predictive models, information that describes each of the trained predictive models, which information includes an indication for each trained predictive model of one or more input types of input data that are compatible with the trained predictive model and an output type of a predictive output that can be generated using the trained predictive model, and instructions that, when executed by the one or more computers, cause the one or more computers to perform operations comprising: receiving a request from a client-subscriber computing system for access to a trained predictive model from the predictive model repository, which trained predictive model can generate a predictive output in response to receiving input data having one or more input types, wherein the one or more input types can be determined from the request; determining from the information that describes each of the trained predictive models that one or more models included in the predictive model repository match the request from the client-subscriber computing system, wherein determining a match is based at least in part on a comparison of the one or more input types determined from the request to input types included in the information that describes the trained predictive models; and providing access to at least one of the one or more models to the client-subscriber computing system; wherein the one or more models that match the request are models that were trained using training data provided by a computing system other than the client-subscriber computing system. 9. The system of claim 1 , wherein: at least one of the one or more input types determined from the request is included in a hierarchy of input types, wherein the at least one input type can be represented by incrementally broader input types by incrementing to higher levels in the hierarchy; and determining a match based at least in part on a comparison of the one or more input types determined from the request to input types included in the information that describes the trained predictive models includes incrementing to one or more higher levels in the hierarchy until an input type that describes a trained predictive model matches the at least one input type determined from the request as represented by incrementally broader input types.