Location-Aware POI Recommendation for Indoor Space by Exploiting WiFi Logs

Algorithm 2

The proposed two-stage approach for indoor POI recommendation.

Require: () User set , POI set , and user’s indoor spatial-temporal

     trajectory ; () Target user

Ensure: POI recommendation list of user .

()    Stage 1: Relation graph construction and inference.

()    for do

()      Calculate initial User-POI relation strength according to Equation (4);

()      Calculate initial User-User relation strength according to Equation (5);

()    end for

()     Construct relation graph ;

()     Obtain transition probability matrix according to Equation (9);

()    Perform random walk with start over to infer User-User relation;

()    Stage 2: POI online recommendation

() Obtain the unvisited POIs set of target user

() for   do

()    Calculate User-POI relation strength according to Equation (10).

() end for

() Rank according to .

() return Select top-K POIs as the recommendation list of .