This document outlines important developments in economics in chronological order, including Alfred Marshall's introduction of marginal utility analysis in 1890, Samuelson's revealed preference theory in 1936, Cournot's duopoly model in 1838, Edgeworth's oligopoly model in 1881, Bertand's oligopoly model in 1883, Stackelberg's work in 1934, and Paul M Sweety's kinked demand curve theory from 1939.

1. Important Chronological Order
By Tanya Bhatia ( Youngest Assistant Professor in Delhi University)

3. Alfred Marshall
 1890 – Marginal Utility Analysis

5. Samuelson 1936 – Revealed Preference
Theory

11.  Ans-4

13. Cournot Duopoly Model - 1838

15. Edgeworth Oligopoly Model - 1881

17. Bert and Oligopoly Model - 1883

20. Stackelberg 1934

22. Kinked Demand Curve – Paul M Sweety 1939

24.  Ans- B