Exploring the relationship between mobile phone call intensity and taxi volume in urban area

As urbanization increases rapidly, there is a need for better understanding of the city and how it functions. Increasing digital data produced by the city´s inhabitants holds great potential for doing so. In this work, an analysis of mobile phone call intensity and taxi volume in Lisbon, Portugal was carried out. With one source of data describes how city operates socially over mobile phone network and the other characterizes urban dynamic in traffic network, we discovered the inter-predictability between them. Based on one month of observation, we found that the variation in the amount of mobile phone calls was strongly correlated with the taxi volume of the previous two hours. Hence taxi volume can be used to predict mobile phone call intensity of the next two hours. In addition, we found that the level of inter-predictability varied across different time of the day; taxi was a predictor during PM hours while mobile phone call intensity became a predictor for taxi volume in AM hours. Strong correlations between these two urban signals were observed during active hours of the day and active days of the week.