Metric integration measures how close each segment is to all others under the definition of metric distance, that is, the metric distance along the lines between the mid-points of two adjacent segments.
Hillier, B. (2009),Spatial sustainability in cities: organic patterns and sustainable forms. In: Koch, D. and Marcus, L. and Steen, J., (eds.) Proceedings of the 7th International Space Syntax Symposium. (pp. p. 1). Royal Institute of Technology (KTH): Stockholm, Sweden. pp. k01.3-4.