May 13, 2020

Propensity Score Matching en R

En este video:

*** Enfoque en la intuición *** 1. Vamos a usar datos en: library(MatchIt - ?matchit). El nombre de la base de datos es data(lalonde) - esta es una muestra. 2. Crear variables dummy. 3. Vamos a calcular propensity scores. 4. Vamos a hacer "match" (pareo) de observaciones usando el paquete "matchit" para encontrar match entre individuos que recibieron el tratamiento e individuos que no. En este caso el tratamiento es un programa de entrenamiento. 5. Vamos a ver los resultados usando dos gráficas: histograma y "jitter". 6. Vamos a comparar estadísticamente la variable de interés (outcome) etre el grupo "match control" y "match treatment". En este caso es la variable ingreso. 7. Vamos a evaluar el balance del metodo de match, con "Love graph." 8. Esto es solo una análisis breve y muy inicial. 9. Sigan mi canal Andres Marroquin. Recursos: Estudio reciente: Podcast:

May 9, 2020

Nuevo video: Gráfica de variables discretas en R

Vean mi nuevo video sobre gráfica de variables discretas en R.

No se olviden de seguir mi canal en YouTube.

May 7, 2020

Nuevo video: Exploración de datos en R usando mtcars

Buenos dias!

En este video hago una introducción básica al análisis de datos en "R." Temas:

Introducción RStudio, Mtcars, histograma, diagrama de dispersión, media, mediana, valor mínimo, valor máximo, nombre de variables, numero de filas

Nuevo Video: Mortalidad en Canada en R

Buenos días!

En este video muestro cómo importar datos en el software "R." También cómo hacer una tabla y  un histograma.

Apr 29, 2020


I have stopped posting in this blog. The reason is that my focus is currently on research.

Sep 14, 2016

Reading Frank H. Knight's "Risk, Uncertainty, and Profit"

The true uncertainty in organized life is the uncertainty in an estimate of human capacity, which is always a capacity to meet uncertainty.
Frank Knight

It is the first time I read RUP. There are a few points I would like to make: 

  1. This is an incredibly good book to understand the origins of entrepreneurial profits. Profits are the reward for an entrepreneur's good judgement when she faces uncertainty. And uncertainty is a kind of risk that can not be measured. 
  2. The book starts with a methodological discussion and Knight indicates the importance of clarity for scientific endeavors. In particular Knight emphasizes that scientists should be transparent about explaining the assumptions of their models. By the way, for Knight there are no economic laws, only tendencies. 
  3. The exploration of assumptions is key for what Knight does in RUP. In particular he describes the perfectly competitive model and explains its assumptions. By doing that he concludes that in this model profits do not exist. However, in reality, profits do exist. And the reason is that in the real world information is not perfect and there are barriers to entry, among other factors -- there is uncertainty! By dissecting the assumptions of a theory (perfect competition) Knight creates a new theory (a theory of profits). 
  4. Once the assumption of perfect information (and others) is relaxed we see the emergence of uncertainty. Uncertainty as explained by Knight has different origins. One is the changing nature of the world, which is partially explained by unpredictable human behavior.
  5. On the one hand, perfect competition is situated in a static world where there are no barriers to entry. Imperfect competition, on the other hand, is situated in a dynamic world. Profits do exist and are taken by entrepreneurs that exercise their good judgment when facing uncertainty. For Knight entrepreneurial good judgement cannot be precisely distinguished from good luck. An interesting topic to discuss is what exactly "good judgment" is, and to what extent good judgment can be taught. 
  6. Once one accepts the importance of good judgement it is easy to understand the implicit theory of the firm in RUP. For Knight entrepreneurs are specialized in maximizing good judgement and they create companies to do so. Entrepreneurs are also specialized in wealth creation. A related point here is that stockholders are the entrepreneurs in modern corporations. 
  7. Who is the entrepreneur? She has "skin in the game," and she is residual claimant of income after the prices of the factors of production (land, capital, and labor) have been imputed. 
  8. It is possible to reduce uncertainty, by grouping different events. Another way (although extreme) to do so is to stop progress. 
  9. Knight argues that human beings maximize wealth, not consumption. He also indicates that human beings are constantly looking to have "interesting" lives. 
  10. Knight was a pioneer of what we call now behavioral economics. He mentions that human beings do not necessary know what they want. Psychology is important and that opens the door for manipulation through marketing. He even mentions what would be known as the "winner's curse." For Knight preferences are not constant, and human beings are often trying to acquire better preferences. 
There is much more in the RUP, and if you have not read it and are interested in entrepreneurship, market process, microeconomics, and risk RUP is a must. Besides, Frank Knight had a fascinating approach to social sciences. He was critical, skeptical, and a heretic in many ways.

Additional readings

These additional readings helped me understand the RUP better and to contextualize Frank Knight and his thinking - they are in no particular order: 

Knight, Frank H. "Abstract Economics as Absolute Ethics." Ethics 76, no. 3 (1966): 163-77.

Knight, Frank H. "Anthropology and Economics." Journal of Political Economy 49, no. 2 (1941): 247-68.

Patinkin, Don. "Frank Knight as Teacher." The American Economic Review 63, no. 5 (1973): 787-810.

Leigh, Arthur H. "Frank H. Knight as Economic Theorist." Journal of Political Economy 82, no. 3 (1974): 578-86.

Economics Is Not All of Life

Kern, William S. "The Lemon Principle, Democratic Politics, and Frank Knight's First Law of Talk." Public Choice 59, no. 1 (1988): 83-87.

Frank H. Knight on the “Entrepreneur Function” in Modern Enterprise

Knight, Frank H. "Imperfect Competition." Journal of Marketing 3, no. 4 (1939): 360-66.

Frank H. Knight and the Chicago School

Langlois, R. N. and Cosgel, M. M. (1993), Frank Knight on Risk, Uncertainty, and the Firm: A New Interpretation. Economic Inquiry, 31: 456–465.

Knight, Frank H. "Laissez Faire: Pro and Con." Journal of Political Economy 75, no. 6 (1967): 782-95.

Wick, Warner. "Frank Knight, Philosopher at Large." Journal of Political Economy 81, no. 3 (1973): 513-15.

Raines, J. Patrick, and Jung Clarence R. "Knight on Religion and Ethics as Agents of Social Change: An Essay to Commemorate the Centennial of Frank H. Knight's Birth." The American Journal of Economics and Sociology 45, no. 4 (1986): 429-39.

Mitchell, Wesley C. The American Economic Review 12, no. 2 (1922): 274-75.

Knight, Frank H. "Profit and Entrepreneurial Functions." The Journal of Economic History 2 (1942): 126-32.

Stigler, George J. "Frank Knight as Teacher." Journal of Political Economy 81, no. 3 (1973): 518-20.

Schultz, T. W. "Frank Knight as Colleague." Journal of Political Economy 81, no. 3 (1973): 516-17.

Watkins, G. P. "Knight's Risk, Uncertainty and Profit." The Quarterly Journal of Economics 36, no. 4 (1922): 682-90.

Raines, J.P. and Jung, C.R. (2009) ‘Monopolies as “Mechanical Defects”: Frank H. Knight on Market Power’, History of Economics Society Bulletin, 10(2), pp. 135–143.

Aug 12, 2016

El Capitalismo del Centavo

Este extraordinary libro es un clásico y fue publicado en español en 1964. Es un estudio detallado de la economía de Panajachel, Sololá, Guatemala. Está basado en el trabajo de campo que el prestigioso antropólogo Sol Tax hizo en la comunidad en los años 30s. En ese tiempo la población de Panajachel no superaba los 2,000 habitantes. 

El autor afirma que la economía de los indígenas de Panajachel puede caracterizarse como “una economía monetaria organizada con las casas individuales como unidades de producción y de consumo, con un mercado fuertemente desarrollado, el cual tiende a ser perfectamente competitivo” p. 51

Sol Tax atribuye la pobreza del pueblo a la falta de tecnología. Es muy posible que las condiciones de vida en los alrededores de Panajachel no hayan cambiado mucho en el tiempo transcurrido desde la investigación de Tax. Creo que este libro es de los más importantes en el área económica que se escribió sobre Guatemala en el siglo 20. De mucho interés para economistas, historiadores, y antropólogos.

Oct 6, 2015

What is language? / Qué es el lenguaje?

…is not a protocol legislated by an authority but rather a wiki that pools the contributions of millions of writers and speakers, who ceaselessly bend the language to their needs and who inexorably age, die, and get replaced by their children, who adapt the language in their turn. (p. 3) 
That is from the excellent book: The Sense of Style by Steven Pinker.

…no es un protocolo legislado por una autoridad sino un wiki que incorpora las contribuciones de millones de escritores y hablantes, quienes sin parar moldean el lenguaje a sus necesidades y quienes inexorablemente embejecen, mueren, y son sustituidos por sus hijos, quienes también adaptan el lenguaje. (p. 3)
 Del excelente libro: The Sense of Style por Steven Pinker.