The Case for Basic Income in developed and underdeveloped countries From what I can tell, the idea of the basic income guarantee is very popular in some circles as an excellent alternative to a lot of modern welfare systems.

Has anybody developed a theoretic or empirical model in which minimum income is tested? In this model, what are the necessary and sufficient conditions for such a model to be preferred to a more traditional alternative?

If anyone has suggested readings on the topic, that would be appreciated as well.
Thanks to densp for identifying this paper.

It refers to a major pilot project undertaken in Namibia

Background:

The Basic Income Grant (BIG) pilot project took place in the Otjivero-Omitara area, about 100 kilometres east of Windhoek. All residents below the age of 60 years receive a Basic Income Grant of N$100 per person per month, without any conditions being attached. The grant is being given to every person registered as living there in July 2007, whatever their social and economic status.

Before the pilot project, the area was characterised by unemployment, hunger and poverty. 

Conclusions:


Since the introduction of the Basic Income Guarantee (BIG), household poverty has dropped significantly. Using the food poverty line, 76% of residents fell below this line in November 2007. This was reduced to 37% within one year of the BIG. 
There was a dramatic increase in economic activity. The rate of those engaged in income generating activities (above the age of 15) increased from 44% to 55%. Thus the BIG enabled recipients to increase their work both for pay, profit or family gain as well as self-employment. The grant enabled recipients to increase their productive income earned, particularly through starting their own small business, including brick-making, baking of bread and dress-making. The BIG contributed to the creation of a local market by increasing households' buying power. This finding contradicts critics' claims that the BIG would lead to laziness and dependency.
Huge reduction in child malnutrition from 42% to 17% in 6 months.
Increase in school attendances (non attendance due to financial reasons dropped 42%)
Drop in crime (theft down 42%)
Estimated cost for a nationwide program in Namibia would be 2-3% of GDP. Not cheap, not unaffordable either.


All thing considered, the author of this report seemed pretty happy with the outcome. There were some issues impacting the data. Since it was a localised study, there was a fair bit of migration towards the treatment area. The long term impacts are not yet known as well.

Additional resources:

Haarmann, Claudia; Haarmann, Dirk; Jauch, Herbert; Mote Hilma et al 2008. Towards a Basic Income Grant for all. Basic Income Grant Pilot Project. First Assessment Report, September 2008. Windhoek

Kameeta, Zephania; Haarmann, Claudia; Haarmann, Dirk; Jauch, Herbert 2007. Promoting employment and decent work for all - Towards a good practice model in Namibia. - Research Paper - Presentation to the United Nations Commission for Social Development. Windhoek 

Haarmann, Claudia; Haarmann, Dirk (ed.) 2005. The Basic Income Grant in Namibia. Resource Book. Windhoek