According to Julian Rotter, the founder of modern-day Social-Cognitive Theory, the choices we make are determined by a combination of two types of variables: Value and Expectancy (see Rotter, 1954, "Social Learning Theory"). Value refers to how much we desire or dread the possible outcomes of a given action. Expectancy refers to how likely we think these possible outcomes are to occur.

Based on this theory, humans should always make the best decisions possible given their current state of knowledge. However, in our everyday life we are often unknowingly swayed in our choices by impulses, habits, and compulsions that are not always in our best interest for attaining what we value the most. The Decider app helps to correct these errors in decision-making by rationally weighing your value and expectancy of the possible positive and negative outcomes for a given action.

Rather than simply comparing the number of pros and cons for a given action, the Decider app calculates a decision score based upon a mathematical formulation of Rotter's Social-Cognitive Theory (for a further description of this formula, please visit https://sites.camosun.ca/michaelpollock/apps/).