The search for a better recommendations software package for websites continues with many firms selling algorithms, which promise a retailer more of an edge. Sheldon Gilbert is founder and chief executive of Proclivity Systems that provides a system to track buying.

Barneys NY - the upscale clothing store chain - claims it has got at least a 10 per cent rise in online revenues by using data mining software, which locates links between certain online behaviour and a greater propensity to purchase something.

Using a system that has been developed by Proclivity Systems, Barneys utilised data about when and where a customer visited its web site and other demographic data to work out on whom it should really focus its e-mail messages.

For instance, an e-mail message declaring sales might go to those particular website visitors who had bought certain products or peculiar types of products previously, but who had done so only when the items were on offer for sale in a particular month. There is a digital trail of interest which is left by customers, helping to track such buying patterns helps marketers effectively focus marketing campaigns.