How can one determine the spending multiplier in an economic model?

To determine the spending multiplier in an economic model, you can use the formula: Spending Multiplier 1 / (1 - Marginal Propensity to Consume). The Marginal Propensity to Consume is the proportion of additional income that a person or household spends rather than saves. By calculating this value, you can find out how changes in spending will impact the overall economy.