91Bxx
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91Bxx Mathematical economics {For econometrics, see 62P20} {Info & Stats}
 91B02 Fundamental topics (basic mathematics, methodology; applicable to economics in general)
 91B06 Decision theory [See also 62Cxx, 90B50, 91A35]
 91B08 Individual preferences
 91B10 Group preferences
 91B12 Voting theory
 91B14 Social choice
 91B15 Welfare economics
 91B16 Utility theory
 91B18 Public goods
 91B24 Price theory and market structure
 91B25 Asset pricing models
 91B26 Market models (auctions, bargaining, bidding, selling, etc.)

91B28 Finance, portfolios, investment  91B30 Risk theory, insurance
 91B32 Resource and cost allocation
 91B38 Production theory, theory of the firm
 91B40 Labor market, contracts
 91B42 Consumer behavior, demand theory
 91B44 Informational economics
 91B50
Equilibrium: general theoryGeneral equilibrium theory  91B51 Dynamic stochastic general equilibrium theory
 91B52 Special types of equilibria
 91B54 Special types of economies
 91B55 Economic dynamics
 91B60
General economic models, trade modelsTrade models  91B62
Dynamic economic models, growth modelsGrowth models  91B64 Macroeconomic models (monetary models, models of taxation)
 91B66 Multisectoral models
 91B68 Matching models
 91B69 Heterogeneous agent models
 91B70 Stochastic models
 91B72 Spatial models
 91B74 Models of realworld systems
 91B76 Environmental economics (natural resource models, harvesting, pollution, etc.)
 91B80 Applications of statistical and quantum mechanics to economics (econophysics)
 91B82 Statistical methods; economic indices and measures
 91B84 Economic time series analysis [See also 62M10]
 91B99 None of the above, but in this section