Diary of a data scientist

A framework for data science management

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Most of what I know about managing data scientists I learned on the job as a data science manager. After four years of practice, I wanted to reflect on what I have learned about data science management and what excellence in this job can be.

Data science management is about much more than hiring good people and getting out of their way. Managing should be about hiring good people and working with them to become even better, manager included.

I do not live up to the description in this essay (yet!), but this is the advice I would have wanted…

Aerial view of La Paz, Bolivia

Every year, I return to my hometown of La Paz in the Andean altiplano of Bolivia. Every time, the city seems unchanged at first. Its downtown core continues hidden in a valley of jagged highland mountains. Its high-altitude air, two and a half miles above sea level, always feels thin and cold.

It is only on the drive from the airport I can notice the change since my last visit. Undeveloped land has been replaced by construction, construction lots have been replaced by houses, houses replaced by buildings, and buildings replaced by even taller buildings. …

The Hindenburg bursts into flames above Lakehurst, New Jersey, on May 6, 1937. (Popperfoto/Getty Images)


In a long day for Pope John Paul II, he before becoming the first pope to enter a mosque by .

Meanwhile, the Catholic missionary Francis Xavier to restore Christianity among Portuguese settlers.

Back in England, ordered every church to have available English-language Bibles.


Spanish armies were busy across the world. They by Incan forces, to the United Kingdom, and joined forces with Germany . …

Este ensayo fue el 22 de marzo de 2021.

Existe siempre una brecha de diferencias entre los deseos de los políticos y los deseos de la ciudadanía. Parte de esta brecha es mala. La causa el interés propio de políticos cínicos y corruptos que quieren poder para beneficiarse (como los recientes actos antidemocráticos del actual gobierno), y la ignorancia de políticos bien intencionados, pero elitistas, que desconocen de la realidad de la ciudadanía.

Si la parte mala de la brecha con un político es demasiado grande — o peor que la de políticos rivales…

Este ensayo fue el 28 de diciembre de 2020.

Mi padre una vez compartió conmigo un refrán del ensayista estadounidense H.L. Mencken: “Para cada problema complejo hay una respuesta clara, simple, y errónea.” Pero la verdad de este refrán no quita la urgencia de enfrentar problemas complejos y la necesidad de tener que simplificarlos para identificar, evaluar, y priorizar posibles soluciones. Estas soluciones no van a ser del todo completas o siempre correctas, pero con esmero, suerte, y su actualización periódica, serán pasos importantes para enfrentar los problemas que intentan abordar.

Con este fin…

The what, why, and how of good process

What is process?

As a manager and a fanboy of organizational behavior, I think a lot about process, the specific sequence of steps a team or organization puts in place to define how a certain end should be achieved. It clarifies how something should be done: from how documents are written (e.g., using a specific template) to how hiring decisions are made (e.g., by unanimous team vote).

Illustration of by

Process is what a team or organization creates when the idiosyncrasy with which something can be done—across people and over time—begins to impose more costs than the costs of standardizing how this something is done.


La tecnología digital ha transformado al mundo. El sector privado ha reconocido este hecho y ha creado la posición ejecutiva de jefe o jefa de tecnología, el o la responsable de entender y confrontar las cuestiones tecnológicas con las que se enfrenta y se enfrentará su empresa. Es una alta posición que típicamente reporta directamente al director ejecutivo ya que las cuestiones tecnológicas son fundamentales no solo para el éxito de la empresa sino para su propia sobrevivencia.

Muchos gobiernos nacionales también han reconocido la importancia de la tecnología y establecido ministerios para impulsarlo en sus países. Argentina tiene al…

I was 15 years old when I read Primal Fear, a novel about a person alleged to have multiple personalities—a condition now called dissociative identity disorder. The psychology depicted in the book impressed me so much that it started me on a decade-long study of the brain and found me, at 25 years old, a doctoral student at Harvard’s Department of Psychology.

But I’d grown disillusioned with the prospect of academic life and curious about other ways to make an impact on the world. A newly-minted psychology Ph.D. …

Diary of a community organizer

Community organizing requires speaking in public people from the community you’re trying to organize and to people outside the community who you’re trying to influence.

Winston Churchill, a renowned orator, wrote in that the best public speeches tend to have five elements.

Precision of diction

This, according to Churchill, is the most important element of an effective public speech: The careful and thoughtful selection of words to convey the precise meaning the speaker intends them to communicate. No more and no less. …

Juan Manuel Contreras, Ph.D.

Data scientist. Behavioral scientist. Progressive rationalist. Bolivian-American.

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