After GrubHub reported better than expected Q3 results but its Q4 guidance was roughly in-line and the stock tumbled about 13% yesterday, JMP Securities analyst Ronald Josey recommends buying the stock on any further weakness. He believes that investors are worried that the benefits of the company's technology "may be fading." However, Josey thinks that the company continues to improve the experience of its users, while it should continue to benefit from its technological upgrades for some time. The analyst reiterates a $47 price target and Outperform rating on the shares.