A machine may implement a recommender that provides recommendations to users. The machine may be configured to present a first version of the recommender configured by various parameters. A user may submit a message to the machine, and the machine may identify a parameter among the various parameters by tokenizing the message and identifying the parameter among the tokens. The machine may then generate a second version of the recommender by modifying the parameter and configuring the second version according to the modified parameter. The machine may then present the first and second versions of the recommender contemporaneously two different portions of the users. By tokenizing a further message received from the users, the machine may evaluate the first and second versions and determine whether the second version is a replacement of the first version.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A method comprising: by a presentation module comprising one or more processors of a machine, presenting a recommender in a first configuration specified by parameters to provide users with recommendations; by a feedback module comprising one or more processors of the machine, identifying a parameter among the parameters by tokenizing a message that corresponds to a user among the users and identifying a token in the message as the parameter; by a modification module comprising one or more processors of the machine, determining a second configuration of the recommender by modifying the parameter; and by an evaluation module comprising one or more processors of the machine, presenting a first subset of the users with the recommender in the first configuration and a second subset of the users with the recommender in the second configuration. 2. The method of claim 1, wherein: the message is a first message submitted by a first user among the users; and the method further comprises: by the feedback module, tokenizing a second message submitted by a second user among the first subset presented with the recommender in the first configuration; and by the evaluation module, determining that second configuration of the recommender is a replacement for the first configuration of the recommender based on the parameter identified from the first message being among tokens of the second message submitted by the second user among the first subset presented with the recommender in the first configuration. 3. The method of claim 1, wherein: the message is a first message submitted by a first user among the users; and the method further comprises: by the feedback module, tokenizing a second message submitted by a second user among the first subset presented with the recommender in the first configuration; and by the evaluation module, determining that second configuration of the recommender is not a replacement for the first configuration of the recommender based on the parameter identified from the first message being among tokens of the second message submitted by the second user among the first subset presented with the recommender in the first configuration. 4. The method of claim 1, wherein: the message is a first message submitted by a first user among the users; and the method further comprises: by the feedback module, tokenizing a second message submitted by a second user among the second subset presented with the recommender in the second configuration; and by the evaluation module, determining that second configuration of the recommender is a replacement for the first configuration of the recommender based on the parameter identified from the first message being among tokens of the second message submitted by the second user among the second subset presented with the recommender in the second configuration. 5. The method of claim 1, wherein: the message is a first message submitted by a first user among the users; and the method further comprises: by the feedback module, tokenizing a second message submitted by a second user among the second subset presented with the recommender in the second configuration; and by the evaluation module, determining that second configuration of the recommender is not a replacement for the first configuration of the recommender based on the parameter identified from the first message being among tokens of the second message submitted by the second user among the second subset presented with the recommender in the second configuration. 6. The method of claim 1, wherein: the identifying of the parameter among the parameters includes determining a sentiment of the message that corresponds to the user; and the determining of the second configuration of the recommender is based on the sentiment of the message being a positive sentiment. 7. The method of claim 1, wherein: the identifying of the parameter among the parameters includes determining a sentiment of the message that corresponds to the user; and the determining of the second configuration of the recommender is based on the sentiment of the message being a negative sentiment. 8. The method of claim 1, wherein: the recommender is configured to provide recommendations of jobs to the users; and the identified parameter is a threshold geographical distance according to which the recommender in the first configuration determines whether to provide a recommendation of a job to the user. 9. The method of claim 1, wherein: the recommender is configured to provide recommendations of social contacts to the users; and the identified parameter is a threshold difference in age according to which the recommender in the first configuration determines whether to provide a recommendation of a social contact to the user. 10. The method of claim 1, wherein: the recommender is configured to provide recommendations of social contacts to the users; and the identified parameter is a threshold minimum age according to which the recommender in the first configuration determines whether to provide a recommendation of a social contact to the user. 11. The method of claim 1, wherein: the recommender is configured to provide recommendations of romantic contacts to the users; and the identified parameter is a threshold geographical distance according to which the recommender in the first configuration determines whether to provide a recommendation of a romantic contact to the user. 12. The method of claim 1, wherein: the recommender is configured to provide recommendations of products to the users; and the identified parameter is a threshold price according to which the recommender in the first configuration determines whether to provide a recommendation of a product to the user. 13. The method of claim 1, wherein: the tokenizing of the message that corresponds to the user includes tokenizing an email received from the user. 14. The method of claim 1, wherein: the tokenizing of the message that corresponds to the user includes tokenizing a blog post published on behalf of the user. 15. The method of claim 1, wherein: the identifying of the parameter among the parameters identifies a unigram token in the tokenized message as the parameter. 16. The method of claim 1, wherein: the identifying of the parameter among the parameters identifies a bigram token in the tokenized message as the parameter. 17. A non-transitory machine-readable storage medium comprising instructions that, when executed by processors of a machine, cause the machine to perform operations comprising: by a presentation module comprising one or more processors of the machine, presenting a recommender in a first configuration specified by parameters to provide users with recommendations; by a feedback module comprising one or more processors of the machine, identifying a parameter among the parameters by tokenizing a message that corresponds to a user among the users and identifying a token in the message as the parameter; by a modification module comprising one or more processors of the machine, determining a second configuration of the recommender by modifying the parameter; and by an evaluation module comprising one or more processors of the machine, presenting a first subset of the users with the recommender in the first configuration and a second subset of the users with the recommender in the second configuration. 18. The non-transitory machine-readable storage medium of claim 17, wherein: the message is a first message submitted by a first user among the users; and the operations further comprise: by the feedback module, tokenizing a second message submitted by a second user among the second subset presented with the recommender in the second configuration; and by the evaluation module, determining that second configuration of the recommender is not a replacement for the first configuration of the recommender based on the parameter identified from the first message being among tokens of the second message submitted by the second user among the second subset presented with the recommender in the second configuration. 19. A system comprising: one or more processors; a memory storing instructions that configure one or more of the processors to perform operations comprising: presenting a recommender in a first configuration specified by parameters to provide users with recommendations; identifying a parameter among the parameters by tokenizing a message that corresponds to a user among the users and identifying a token in the message as the parameter; determining a second configuration of the recommender by modifying the parameter; and presenting a first subset of the users with the recommender in the first configuration and a second subset of the users with the recommender in the second configuration. 20. The system of claim 19, wherein: the message is a first message submitted by a first user among the users; and the operations further comprise: tokenizing a second message submitted by a second user among the second subset presented with the recommender in the second configuration; and determining that second configuration of the recommender is not a replacement for the first configuration of the recommender based on the parameter identified from the first message being among tokens of the second message submitted by the second user among the second subset presented with the recommender in the second configuration.