Contagion of accounting methods: evidence from stock option expensing

I examine how a firm’s accounting methods can be influenced by the choices of other firms, which I label contagion. I model accounting method choice as a combination of intrinsic propensities to adopt a method and contagion effects. I predict contagion of accounting methods occurs for two reasons: (1) adoption decisions of other firms are informative for the adoption decision, and (2) prior adoptions change the net benefits of the decision. I test these predictions in the stock option expensing setting where firms had the choice to use the intrinsic or fair value method. Using a firm-level diffusion model, I document evidence consistent with my predictions.