1. DATA SCIENCE MIS0855 | Spring 2016 Science and Data Science SungYong Um Sungyong.um@temple.edu

2. Today’s Goal  Basic Concepts Data science Hypothesis  Examples

3. What is data science? Compare it to the definition of science: knowledge about or study of the natural world based on facts learned through experiments and observation (Merriam-Webster)

4. What is data science? Why do you think this course is called “Data Science”? What is science?  A collection of proven knowledge that  explains what is happening and  predicts what will happen.

5. What makes knowledge actionable ? Why is that a goal? How does big data facilitate this?

6. The dangers of (big data) analytics It’s easy to find what’s not really there The direction of causality can be tricky “Dirty” data is everywhere

7. For knowledge to be useful for informed decision making, 1. It needs to be based on facts substantiated by data and information. 2. How to build knowledge from data and information in a scientific manner? 3. By devising formal hypotheses and testing them with data

8. So…Start with a hypothesis “The testable predictions from an idea” – Rhett Allain, Wired With an underlying rationale that makes sense How is this different from a theory? And what about Allain’s use of “model?” “…all models are wrong, but some are useful.” – George Box, Empirical Model-Building and Response Surfaces Main idea: Don’t guess!

9. 1. Testable – be able to be measured by data 2. Falsifiable – be able to be proven false by data 3. Grounded in a theory – be able to be explained by sensible rationale(s)

10. A hypothesis should be GoodBad Testable iPhone users download more apps each month than Android users. iPhone users are better than Android users. Falsifiable There are no vampires living in Louisiana. There are vampires living in Louisiana. Grounded in a rationale Students who attend class more often get better grades. Students who are taller attend class more often.

11. Any Theory or Rationale Behind This? (1/2)

12. Any Theory or Rationale Behind This? http://www.ozy.com/acumen/in-sickness-and-in-health-but-not-in-debt/38366?utm_source=A1&utm_medium=pp&utm_campaign=pp https://www.pinterest.com/pin/218072806933122983/

13. Create your own hypotheses “Temple University is greater than Drexel University.” How would you make this more testable? What is the theory/rationale behind your hypothesi(e)s? http://www.communityenergyinc.com/temple/ http://www.tiffanysbakeryphilly.com/university-delivery/drexel-university

14. In-Class Exercise – What is a Theory or Rationale Behind This? http://www.ozy.com/acumen/in-sickness-and-in-health-but-not-in-debt/38366?utm_source=A1&utm_medium=pp&utm_campaign=pp