We analyze under which conditions a given vector field can be disaggregated as a linear combination of gradients. This problem is typical of aggregation theory, as illustrated by the literature on the characterization of aggregate market demand and excess demand. We argue that exterior...

Is general equilibrium theory empirically testable? Our perspective on this question differs from the standard, Sonnenschein-Debreu-Mantel (SDM) viewpoint. While SDM tradition considers aggregate (excess) demand as a function of prices, we assume that what is observable is the equilibrium price...

We consider <InlineEquation ID="IEq1"> <EquationSource Format="TEX">$$H$$</EquationSource> <EquationSource Format="MATHML"> <math xmlns:xlink="http://www.w3.org/1999/xlink"> <mi>H</mi> </math> </EquationSource> </InlineEquation> expected utility maximizers that have to share a risky aggregate multivariate endowment <InlineEquation ID="IEq2"> <EquationSource Format="TEX">$$X\in {\mathbb {R}}^{N}$$</EquationSource> <EquationSource Format="MATHML"> <math xmlns:xlink="http://www.w3.org/1999/xlink"> <mrow> <mi>X</mi> <mo>∈</mo> <msup> <mrow> <mi mathvariant="double-struck">R</mi> </mrow> <mi>N</mi> </msup> </mrow> </math> </EquationSource> </InlineEquation> and address the following two questions: does efficient risk-sharing imply restrictions on the form of individual consumptions as a...</equationsource></equationsource></inlineequation></equationsource></equationsource></inlineequation>