I am currently working on *Models in political economy*, which presents some of the main models in the field of political economy. Political economy, as the term is used by economists, is the study of the methods by which societies make collective decisions, whether by elections or by oligarchs, autocrats, or dictators. The book covers the areas of collective choice, voting, electoral competition, bargaining, and rebellion.

All the models are defined precisely and the results are proved in detail. All the formal content — definitions and results — is contained in boxes. This material is self-contained and can in principle be read independently of the informal discussion. Every term in these boxes that has a technical meaning, other than basic mathematical terms, is hyperlinked to its definition. If you click on the hyperlink you are taken to the definition. Your pdf viewer probably allows you to return to where you were by holding the `Alt`

key down and pressing the `←`

key (the left arrow key on the cursor pad).

## current draft

Here is the current draft:

If you find mistakes, omissions, or hard-to-follow arguments, or have other suggestions for improvements, please let me know (`martin.j.osborne`

on `gmail`

).

## versions

- 2023.2.28
- Addition of single-peakedness on trees in Chapter 1, simplification of Section 3.2 in Chapter 3 (restriction to case in which some coats are less than 1/2 and some are greater than 1/2), and many improvements in Chapter 5, including the addition of Section 5.4.
- 2023.1.27
- Improvements in Chapter 1 and correction of error in Proposition 4.3c.
- 2023.1.20
- Improvements in Chapters 1 and 2.
- 2023.1.9
- Correction of error in synopsis for Chapter 3 plus correction of typos.
- 2023.1.8
- Improvements in Chapter 1 (most significant: single-crossing, proofs of Propositions 1.2 and 1.3).
- 2022.12.31
- Addition of subtitle.
- 2022.12.28
- First complete draft.