... known as dis-saving spending. MPC = Marginal propensity to consume. This is the change in consumption divided by the change in income, or in other words, it determines the slope of the consumption ... to interpret it. 1. DEFINITIONS1.1. IncomeThere are two main types of income, which can be listed as personal income and disposable income.1.1.1. Personal income (PI)Personal income is the ... 10β=, that is, the intercept is not significant.- If the variable X1 (X1 = 1) is omitted, or in other words the intercept 10β=, we obtain the following result when running a regression...