Disclaimer. Don't rely on these old notes in lieu of reading the literature, but they can jog your memory. As a grad student long ago, my peers and I collaborated to write and exchange summaries of political science research. I posted them to a wiki-style website. "Wikisum" is now dead but archived here. I cannot vouch for these notes' accuracy, nor can I say who wrote them.
Muller and Seligson. 1987. Inequality and insurgency. American Political Science Revew 81 (June): 425-452.
Argument: Land maldistribution isn't the cause; it is only a symptom of a larger problem, namely, income disparity. Four premises: 1. Inequality generates discontent; 2. some societies are more inegalitarian than others; 3. land maldistribution and income disparity are not necessarily closely correlated, so they can be separately estimated; 4. regardless of disparity and discontent, it is more difficult to mobilize rural communities than urban populations. THUS: 1. Higher levels of inequality nationwide "raises the probability that at least some dissident groups will be able to organize for aggressive collective action" (b/c there is a larger pool of discontented people and b/c it may therefore be easier for urban revolutionaries and rural peasants to ally together). 2. Land maldistribution is relatively unimportant; unless there is general income inequality (which creates urban revolutionaries who can mobilize the discontented peasants), political violence will remain low.
Model on page 431 shows the key hypotheses: (1) Hypothesis they wish to disprove: agrarian inequality matters. Their model shows it as merely a part of income inequality (in addition to landlessness). What they really want to show is that income inequality matters but, as shown by the arrows, they will also control for landlessness and agrarian inequality. (2) The "x" isn't a variable, it's a multiplication sign. Semi-repressiveness interacts with income inequality. Overly repressive regimes prevent violence; free regimes make peaceful mobilization a better deal. Thus, semi-repressiveness is a necessary condition of violence. Income inequality is a sufficient condition (as I take it, at least). (3) Other hypotheses are clear enough.
To really understand the model on page 431 (with all its hypothesized causal arrows), compare it with the observed model on page 442 (which shows only those causal arrows that are empirically supported).
Measurement: on pg 434 they give an argument against using GINI coefficients for income disparity. Why, then, do they use GINI coefficients for land disparity?
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