Business cycle asymmetry and input-output structure: The role of firm-to-firm networks
利用跨国和企业层面数据，研究发现投入产出网络密度越大，产出增长越呈负偏态；通过多部门模型揭示，生产互补性下密集网络放大负面冲击，而替代性下则分散风险。
We study the network origins of business cycle asymmetries using cross-country and administrative firm-level data. At the country level, we document that countries with a larger number of non-zero intersectoral linkages (denser networks) display a more negatively skewed cyclical component of output. At the firm level, we find that firms with a larger number of suppliers and customers (degrees) display a more negatively-skewed distribution of their output growth. To rationalize these findings, we construct a multisector model with input-output linkages and show that the relationship between output skewness and network density naturally arises once we consider non-linearities in production. In an economy with low production flexibility (inputs are gross complements), denser production structures imply that relying on more inputs becomes a risk that further amplifies the effects of negative productivity shocks. The opposite holds if firms display high production flexibility (inputs are gross substitutes): having more inputs to choose from becomes an opportunity to diversify the effects of negative productivity shocks. We calibrate the model using our rich firm-to-firm network Chilean data and show that more connected firms experience larger declines in output in response to a COVID-19 shock, consistent with the data. We also show that, as in the data, the cross-sectional distribution of output growth in the model displays a fatter left tail during downturns. The previous result is shaped by the interplay between production complementarities and network interconnectedness, rather than by the asymmetry of the shocks. The size of the shock determines the strength of the relationship between degrees and output decline, which highlights the importance of non-linearities and the limitations of local approximations.