Investors flocked to shares of Audible ( ADBL) on Wednesday, a day after the company narrowed its fourth-quarter loss and beat analysts' projections on both the top and bottom lines. The audio book company's stock shot up 212% in recent trading, tacking on $1.73 to $9.68 in heavy volume. The Street's reaction to the quarter was largely positive, with several Wall Street analysts boosting their ratings on the shares to buy. Still, at least one analyst said the huge price jump was likely due to the "proverbial short squeeze." For the fourth quarter , Audible posted a loss of $700,000, or 3 cents a share, narrowing its loss of $2.2 million, or 9 cents a share, in the year-ago quarter. Analysts polled by Thomson First Call expected a loss of 7 cents a share. Revenue totaled $23.3 million, up from $18.3 million in the same period a year ago and beating the $21.9 million analysts' consensus forecast. Audible executives said late Tuesday that they are focusing on recruiting higher-paying monthly members, who pay a $15-to-$23 monthly fee with more benefits, rather than pitching a basic a la carte annual plan for $9.95 a year. The shift in strategy makes sense, some analysts noted. "Bookings per member increased in Q4 to $70.50/sub from $64.60/sub last quarter," wrote Jefferies analyst Ross MacMillan on Wednesday. "Success with the higher average revenue per user subscription plans are driving higher deferred revenue and net income."