This refers to the distinction between measuring a variable directly (e.g. by asking a participant to rate their level of anxiety) and indirectly (e.g. by observing changes in physiological markers like heart rate or skin conductance).
This refers to the distinction between measuring a variable directly (e.g. by asking a participant to rate their level of anxiety) and indirectly (e.g. by observing changes in physiological markers like heart rate or skin conductance).