Hi,
I'm gettin into mahout through the reading of Mahout in action. I'm pretty curious about this sentence: [talking about item-based an user-based reccomendation systems] "They do have notably different properties. For instance, the running time of an item-based recommender scales up as the number of items increases, whereas a user-based recommender’s running time goes up as the number of users increases. This suggests one reason that you might choose an item-based recommender: if the number of users is relatively low compared to the number of items, the performance advantage could be significant." How would the item-based recommender be a good choice with a huge number of items if the item-based recommender's cost grows with the number of items? thanks -- Claudio Martella Digital Technologies Unit Research & Development - Analyst TIS innovation park Via Siemens 19 | Siemensstr. 19 39100 Bolzano | 39100 Bozen Tel. +39 0471 068 123 Fax +39 0471 068 129 [email protected] http://www.tis.bz.it Short information regarding use of personal data. According to Section 13 of Italian Legislative Decree no. 196 of 30 June 2003, we inform you that we process your personal data in order to fulfil contractual and fiscal obligations and also to send you information regarding our services and events. Your personal data are processed with and without electronic means and by respecting data subjects' rights, fundamental freedoms and dignity, particularly with regard to confidentiality, personal identity and the right to personal data protection. At any time and without formalities you can write an e-mail to [email protected] in order to object the processing of your personal data for the purpose of sending advertising materials and also to exercise the right to access personal data and other rights referred to in Section 7 of Decree 196/2003. The data controller is TIS Techno Innovation Alto Adige, Siemens Street n. 19, Bolzano. You can find the complete information on the web site www.tis.bz.it.
