1998 Dodge Neon brakes sticking

My brakes are randomly sticking, I believe in the front drivers side. I can smell pad burning. Only happens about once or twice a month.I susoected the driver front caliper was seizing so I replaced it. Problem still there. I also replace the brake hose. When it sticks the pedal gets hard and it pulls to the right if I apply the brakes. Should I replace the other caliper or suspect the master cylinder or proportioning valve.