Clustering Method Using Item Preference Based on RFM for Recommendation System in U-Commerce

A materials demand model with ordering quantity of past and recency of ordering time

“…Then Q log follows normal distribution and its pdf is We consider the recency of ordering time (denoted as R) is demonstrated as renew process [9]. Then, according to the renew process in statistic [9][10][11][12], we can calculate its pdf and cumulative distribution function (cdf).…”

“…Then, according to the renew process in statistic [9][10][11][12], we can calculate its pdf and cumulative distribution function (cdf). First, we assume the purchase interval time is a random variable which follows exponential distribution [8].…”

“…The concept of recency of ordering time stands on the view of point in RFM which is a method used for analyzing customer value [5][6][7][8][9]. R index is to explore how recently the customer makes his purchase behavior [5,8,9].…”

“…R index is to explore how recently the customer makes his purchase behavior [5,8,9]. F index is to discuss how often this customer purchase [6][7].…”

“…F index is to discuss how often this customer purchase [6][7]. R index is demonstrated by how much money this customer spends [6,8,9]. We extend the R index to the recency of ordering time which is the time length between the last ordering (purchase) time from the upstream in the observation period and the observing deadline [8].…”