Anchoring as System 2 Adjustment

Key Insight

One mechanism underlying anchoring effects involves a deliberate, conscious process of adjustment by System 2. When presented with an anchor, people start from that number, assess if it's too high or too low, and then mentally 'move' their estimate in the appropriate direction. However, this adjustment process is typically insufficient, stopping prematurely when people are no longer certain they should move further.

Examples of insufficient adjustment include drivers maintaining too high a speed on city streets after exiting a highway, failing to fully adjust from the higher-speed anchor. Similarly, a teenager turning down loud music to a 'reasonable' volume may still leave it too loud for a parent, as they have not adjusted sufficiently from the high volume anchor.

Evidence confirms that this adjustment is an effortful operation. People adjust less and stay closer to the anchor when their mental resources are depleted, such as when their memory is overloaded or they are slightly intoxicated. Conversely, being instructed to physically reject an anchor (e.g., shaking one's head) causes greater adjustment. This shows that System 2's deliberate effort to adjust is prone to failure or laziness.