Rivian bulls are betting on the wrong numbers.Investors in Rivian Automotive (RIVN 5.25%) had a rough week, as the electric truck stock sank slowly but surely below $10 after the company issued a disappointing "earnings" report -- a report that featured no earnings at all, but rather$1.45 per share in losses.Despite the bad news, however, Cantor Fitzgerald analyst Andres Sheppard came out with a prediction last Wednesday: Within 12 months, Rivian stock will soar 50% to close at $15 a share. Is Rivian stock ...