How do I become a data scientist?

data science -1

Answer by Alex Kamil:

Strictly speaking, there is no such thing as "data science" (see What is data science? ). See also: Vardi, Science has only two legs: http://portal.acm.org/ft_gateway…

Here are some resources I've collected about working with data, I hope you find them useful  (note: I'm an undergrad student, this is not an expert opinion in any way).

1) Learn about matrix factorizations

• Take the Computational Linear Algebra course (it is sometimes called Applied Linear Algebra or Matrix Computations or Numerical Analysis or Matrix Analysis and it can be either CS or Applied Math course). Matrix  decomposition algorithms are fundamental to many data mining applications and are usually underrepresented in a standard "machine learning" curriculum. With TBs of data traditional tools such as Matlab become not suitable for the job, you cannot just run eig() on Big Data. Distributed matrix computation packages such as those included in Apache Mahout [1] are trying to fill this void but you need to understand how the numeric algorithms/LAPACK/BLAS routines [2][3][4][5] work in order to use them properly, adjust for special cases, build your own and scale them up to terabytes of data on a cluster of commodity machines.[6] Usually numerics courses are built upon undergraduate algebra and calculus so you should be good with prerequisites.  I'd recommend these resources for self study/reference material:
• See Jack Dongarra : Courses and What are some good resources for learning about numerical analysis?

2) Learn about distributed computing

• It is important to learn how to work with a Linux cluster and how to design scalable distributed algorithms if you want to work with big data (Why the current obsession with "big" data? ).
• Crays and Connection Machines of the past can now be replaced with farms of cheap cloud instances, the computing costs dropped to less than $1.80/GFlop in 2011 vs $15M in 1984: http://en.wikipedia.org/wiki/FLOPS .
• If you want to squeeze the most out of your (rented) hardware it is also becoming increasingly important to be able to utilize the full power of multicore  (see http://en.wikipedia.org/wiki/Moo… )
• Note: this topic is not part of a standard Machine Learning track but you can probably find courses such as Distributed Systems or Parallel Programming in your CS/EE catalog. See distributed computing resources, a systems course at UIUC, key works, and for starters: Introduction to Computer Networking.

• After studying the basics of networking and distributed systems, I'd focus on distributed databases, which will soon become ubiquitous with the data deluge and hitting the limits of vertical scaling.  See key works,  research trends and for starters: Introduction to relational databases and Introduction to distributed databases (HBase in Action).

3) Learn about statistical analysis

• Start learning statistics by coding with R: What are essential references for R? and experiment with real-world data: Where can I find large datasets open to the public?
• Cosma Shalizi compiled some great materials on computational statistics, check out his lecture slides, and also What are some good resources for learning about statistical analysis?

• I've found that learning statistics in a particular domain (e.g. Natural Language Processing) is much more enjoyable than taking Stats 101. My personal recommendation is the course by Michael Collins at Columbia (also available on Coursera).
• You can also choose a field where the use of quantitative statistics and causality principles [7]  is inevitable, say molecular biology [8], or a fun sub-field such as cancer research [9], or even narrower domain, e.g. genetic analysis of tumor angiogenesis [10] and try answering important questions in that particular field, learning what you need in the process.

4) Learn about optimization

• This subject is essentially prerequisite to understanding many Machine Learning and Signal Processing algorithms, besides being important in its own right.
• Start with Stephen P. Boyd's video lectures and also What are some good resources to learn about optimization?

5) Learn about machine learning

• Before you get to think about algorithms look carefully at the data and select features that help you filter signal from noise. See this talk by Jeremy Howard : At Kaggle, It’s a Disadvantage To Know Too Much
• Also see  What are some good resources to learn about machine learning? and What are some introductory resources for learning about large scale machine learning? Why?

• Statistics vs. machine learning, fight!:  http://brenocon.com/blog/2008/12…
• You can structure your study program according to online course catalogs
  and curricula of MIT, Stanford or other top schools. Experiment with
  data a lot, hack some code, ask questions, talk to good people, set up a web crawler in your garage: The Anatomy of a Search Engine
• You can join one of these startups and learn by doing: What startups are hiring engineers with strengths in machine learning/NLP?
• The alternative (and rather expensive) option is to enroll in a CS
  program/Machine Learning track if you prefer studying in a formal
  setting. See: What makes a Master's in Computer Science (MS CS) degree worth it and why?
• Try to avoid overspecialization. The breadth-first approach often works best when learning a new field and dealing with hard problems, see the Second voyage of HMS Beagle on the adventures of an ingenious young data miner.

6) Learn about information retrieval

• Machine learning Is not as cool as it sounds: http://teddziuba.com/2008/05/mac…
• What are some good resources to get started with Information Retrieval? Why?

7) Learn about signal detection and estimation

• This is a classic topic and "data science" par excellence in my opinion.
  Some of these methods were used to guide the Apollo mission or detect
  enemy submarines and are still in active use in many fields. This is
  often part of the EE curriculum.
• Good references are Robert F. Stengel' lecture slides on optimal control and estimation: Rob Stengel's Home Page, Alan V. Oppenheim's Signals and Systems. and What are some good resources for learning about signal estimation and detection? A good topic to focus on first is Kalman filter, widely used for Time series forecasting.
• Talking about data, you probably want to know something about information: its transmission, compression and filtering signal from noise.  The methods developed by communication engineers in the 60s (such as Viterbi decoder, now used in about a billion cellphones) are applicable to a surprising variety of data analysis tasks, from Statistical machine translation to understanding the organization and function of molecular networks. A good resource for starters is Information Theory and Reliable Communication: Robert G. Gallager: 9780471290483: Amazon.com: Books. Also What are some good resources for learning about information theory?

8) Master algorithms and data structures

• What are the most learner-friendly resources for learning about algorithms?

9) Practice

• Getting In Shape For The Sport Of Data Science
• Carpentry: http://software-carpentry.org/
• What are some good "toy problems" in data science?
• Tools: Which are some of the best Data Analysis tools?
• Where can I find large datasets open to the public?

If you do decide to go for a Masters degree:

10) Study Engineering

I'd go for CS with a focus on either IR or Machine Learning or a combination of both and take some systems courses along the way. As a "data scientist" you will have to write a ton of code and probably develop distributed algorithms/systems to process massive amounts of data. MS in Statistics will teach you how to do modeling and regression analysis etc, not how to build systems, I think the latter is more urgently needed these days as the old tools become obsolete with the avalanche of data. There is a shortage of engineers who can build a data mining system from the ground up. You can pick up statistics from books and experiments with R (see item 3 above) or take some statistics classes as a part of your CS studies.

Good luck.

[1] http://mahout.apache.org/
[2] http://www.netlib.org/lapack/
[3] http://www.netlib.org/eispack/
[4] http://math.nist.gov/javanumeric…
[5] http://www.netlib.org/scalapack/
[6] http://labs.google.com/papers/ma…
[7] Amazon.com: Causality: Models, Reasoning and Inference (9780521895606): Judea Pearl: Books
[8] Introduction to Biology , MIT 7.012 video lectures
[9] Hanahan & Weinberg, The Hallmarks of Cancer, Next Generation: Page on Wisc
[10] The chaotic organization of tumor-associated vasculature, from The Biology of Cancer: Robert A. Weinberg: 9780815342205: Amazon.com: Books, p. 562

How do I become a data scientist?