%0 Journal Article %T Cybersecurity Investment Guidance: Extensions of the Gordon and Loeb Model %A Scott Farrow %A Jules Szanton %J Journal of Information Security %P 15-28 %@ 2153-1242 %D 2016 %I Scientific Research Publishing %R 10.4236/jis.2016.72002 %X Extensions of the Gordon-Loeb [1] and the Gordon-Loeb-Lucyshyn-Zhou [2] models are presented based on mathematical equivalency with a generalized homeland security model. The extensions include limitations on changes in the probability of attack, simultaneous effects on probability and loss, diversion of attack, and shared non-information defenses. Legal cases are then investigated to assess approximate magnitudes of external effects and the extent they are internalized by the legal system. %K Cybersecurity %K Investment %K Externality %K Log-Convexity %K Law %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=64591