1. A computer implemented method of recommending products and services comprising the digital processing steps of: processing user profiles to extract keywords; identifying which keywords commonly occur together in the same user profiles, where identifying which keywords commonly occur together in the same user profiles includes computing the frequency with which a keyword appears in conjunction with another keyword including: computing the degree to which the two keywords tend to occur together; determining a ratio indicating the frequency with which the two keywords appear together; determining a correlation index indicating the likelihood that users interested in one of the keywords will be interested in the other keyword, as compared to an average profile; and determining a percentage of co-occurrence for each keyword, where the percentage of co-occurrence is used to determine a correlation ratio indicating how often a co-occurring keyword is present; and expanding a search query with additional search terms related to the search query, where the additional search terms are determined using one or more of the identified co-occurring keywords.
1. A computer implemented method of recommending products and services comprising the digital processing steps of: processing user profiles to extract keywords; identifying which keywords commonly occur together in the same user profiles, where identifying which keywords commonly occur together in the same user profiles includes computing the frequency with which a keyword appears in conjunction with another keyword including: computing the degree to which the two keywords tend to occur together; determining a ratio indicating the frequency with which the two keywords appear together; determining a correlation index indicating the likelihood that users interested in one of the keywords will be interested in the other keyword, as compared to an average profile; and determining a percentage of co-occurrence for each keyword, where the percentage of co-occurrence is used to determine a correlation ratio indicating how often a co-occurring keyword is present; and expanding a search query with additional search terms related to the search query, where the additional search terms are determined using one or more of the identified co-occurring keywords. 10. A computer implemented method as in claim 1 wherein the search query is a request for a gift recommendation or a trip recommendation.