Traditional microeconomics makes greater assumptions about the economic actors (that they are utility maximizing, have perfect information, in competitive markets with many participants, etc.) and based on those assumptions it is accurate in describing what happens mathematically. Macroeconomics doesn’t make as many assumptions because it’s based on the observed behavior of market participants in aggregate (GDP is just the sum of the four components of GDP, wages can be proven to be sticky the downward direction, and such), but macroeconomists are wrong or surprised all the time about the path of GDP and unemployment.
Note that I don’t necessarily agree with this characterization, but that’s what he’s going for.
Traditional microeconomics makes greater assumptions about the economic actors (that they are utility maximizing, have perfect information, in competitive markets with many participants, etc.) and based on those assumptions it is accurate in describing what happens mathematically. Macroeconomics doesn’t make as many assumptions because it’s based on the observed behavior of market participants in aggregate (GDP is just the sum of the four components of GDP, wages can be proven to be sticky the downward direction, and such), but macroeconomists are wrong or surprised all the time about the path of GDP and unemployment.
Note that I don’t necessarily agree with this characterization, but that’s what he’s going for.