Anticipator is a hype word for thermostat manufacturers. It does not anticipate; but the manufacturers would like to think it is so sophisticated that it actually does what a human can (for $12 no less - like, get real.)
The anticipator in a thermostat is an electric heater that raises the temperature of the bimetal to over-ride the constructed differential to result in a narrower range of opening and closing contact. It is actually a differential adjustment or compensator (Ausgleich)(Raumtemperature mit Ruckfuhrung)(genauere Regelverhalten); so you might start there.