Fowler, MJ 2013, 'Structural data bias in the digital age', in PM Dight (ed.), Slope Stability 2013: Proceedings of the 2013 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering, Australian Centre for Geomechanics, Perth, pp. 219-225, https://doi.org/10.36487/ACG_rep/1308_09_Fowler (https://papers.acg.uwa.edu.au/p/1308_09_Fowler/) Abstract: This paper presents a description of data bias associated with both conventional and digital mapping of rock mass discontinuities. Digital mapping of rock mass discontinuities is now commonplace with, for instance, borehole imaging, LiDAR and photogrammetry becoming standard tools for geotechnical investigations. Rock mass discontinuities are a major control on the design of hard rock slopes and underground openings. Understanding the inherent bias of different sampling methods is an important aspect of building reliable engineering geological models.