Analyzing and interpreting user positioning data

Abstract

In a computer system, a pedestrian dataset that indicates position fixes for several portable devices is received, such that each portable device corresponds to a respective pedestrian. Raw heat scores for several geographic units of equal size are generated based on the pedestrian dataset, each raw heat score being indicative of a number of position fixes in the corresponding geographic unit. A selection of a geographic area that contains some of the geographic units is received, and normalized heat scores for these geographic units are generated based on at least some of the generated raw heat scores.

What is claimed is: 
     
         1 . A method in a computer system for generating pedestrian heat scores, the method comprising:
 receiving a pedestrian dataset that indicates position fixes for a plurality of portable devices, wherein each portable device corresponds to a respective pedestrian;   generating raw heat scores for a plurality of geographic units of equal size based on the pedestrian dataset, each raw heat score being indicative of a number of position fixes in the corresponding geographic unit;   receiving a selection of a geographic area that contains a subset of the plurality of geographic units; and   generating normalized heat scores for the subset of the plurality of geographic units based on at least some of the generated raw heat scores.   
     
     
         2 . The method of  claim 1 , further comprising:
 generating a visual representation of the generated normalized heat scores; and   causing the visual representation of the generated normalized heat scores to be displayed on a digital map of the selected geographic area.   
     
     
         3 . The method of  claim 2 , wherein generating the visual representation of the normalized heat scores includes indicating different normalized heat scores using at least one of:
 (i) different colors,   (ii) different line thicknesses, and   (iii) different graphic markers.   
     
     
         4 . The method of  claim 1 , wherein receiving the pedestrian dataset includes:
 receiving, for a first subset of the plurality of portable devices, position tracks made up of successive position fixes, and   receiving, for a second subset of the plurality of portable devices, single position fixes.   
     
     
         5 . The method of  claim 4 , wherein for a target geographic unit included in the subset of the plurality of geographic units, generating the raw heat score includes:
 multiplying a number of position tracks passing through the target geographic unit by a first weight to generate a first product,   multiplying a number of single location fixes in the target geographic unit by a second weight to generate a second product, and   generating the raw heat score using the first product and the second product.   
     
     
         6 . The method of  claim 4 , wherein for a target geographic unit included in the subset of the plurality of geographic units, generating the raw heat score includes:
 determining whether a trajectory associated with one of the position tracks passes through the target geographic unit, wherein none of the position fixes included in the position track is in the target geographic unit, and   in response to determining that the trajectory passes through the target geographic unit, automatically incrementing a raw score of the target geographic unit.   
     
     
         7 . The method of  claim 1 , wherein each geographic unit is one of (i) a square cell of a fixed size or (ii) a road segment of a fixed length. 
     
     
         8 . The method of  claim 1 , wherein to generate a normalized heat score for a target geographic unit included in the subset of the plurality of geographic units, the method includes:
 selecting a normalization radius, and   generating the normalized heat score for the target geographic unit based on raw heat scores of geographic units that lie within the normalization radius of the target geographic unit.   
     
     
         9 . The method of  claim 8 , further comprising displaying a digital map of the selected geographic area, wherein the normalization radius is selected based on a zoom level at which the digital map is being displayed. 
     
     
         10 . The method of  claim 1 , wherein generating the normalized heat scores
 to generate a normalized heat score for a target geographic unit included in the subset of the plurality of geographic units, the method includes:   displaying, within a viewport, a digital map of the selected geographic area that includes the target geographic unit,   generating the normalized heat score for the target geographic unit based on raw heat scores of geographic units corresponding to the geographic area.   
     
     
         11 . The method of  claim 1 , wherein for a target geographic unit included in the subset of the plurality of geographic units, generating a normalized heat score includes:
 selecting a subset of the plurality of geographic units based at least on proximity to the target geographic unit,   generating a histogram using the raw heat scores of the selected geographic units, and   generating the normalized heat score using the histogram.   
     
     
         12 . The method of  claim 1 , wherein receiving the pedestrian dataset includes receiving a plurality of time-specific subsets of the pedestrian dataset.