Should we teach data mining without using a programming language?

Should data mining newcomers have to learn programming at the same time? Here is a contrarian view, which advocates a GUI (“drag and drop”) environment. Even though the popularity of R (and recently, Python) is increasing.  

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Showing linear regression coefficients

I have just finished my Big Data course for 2017, and noted some concepts that I want to teach better next year. One of them is how to interpret and use the coefficient estimates from linear regression. All economists are familiar with dense tables of coefficients and standard errors, but they require experience to read, and are not at all intuitive. Here is a more intuitive and useful way to display the same information. The blue dots show the coefficient estimates, while the lines show +/- 2 standard errors on the coefficients. It’s easy to see that the first two coefficients are “statistically significant at the 5% level”, the third one is not, and so on. More important, the figure gives a clear view

Coef plot from strengejacke Bof the relative importance of different variables in determining the final outcomes.

The heavy lifting for this plot is done by the function sjp.lm from the sjPlot library. The main argument linreg is the standard results of a linear regression model, which is a complex list with all kinds of information buried in it.  Continue reading

Schumpeter: The University of Chicago worries about a lack of competition | The Economist

Its economists used to champion big firms, but the mood has shifted

Source: Schumpeter: The University of Chicago worries about a lack of competition | The Economist

There is an emerging consensus among economists that competition in the economy has weakened significantly. That is bad news: it means that incumbent firms may not need to innovate as much, and that inequality may increase if companies can hoard profits and spend less on investment and wages.

Yes, I certainly see this in tech fields.The double consequences are scary.

Thanks to colleague Prof. Liz Lyons for suggesting this.

Style by subscription: Why clothing-to-your door is so popular – Silicon Valley

I’m going to list some oddball potential case study opportunities for my students here. (I’m teaching 3 courses in April, all requiring papers!).

Having a computer and a person you’ve never met pick clothes out for you, based on a style questionnaire and your social media photos, seems an odd concept. But San Francisco’s Stitch Fix and Le To…

Source: Style by subscription: Why clothing-to-your door is so popular – Silicon Valley

Leave Your Laptops at the Door to My Classroom 

The research on this seems pretty overwhelming: laptops and cell phones in class hurt learning. Related issue: learning to listen.

Unfortunately in my more quant courses, they can be necessary at times. But if I had a way to turn off the Internet, I certainly would. (FCC makes wireless jamming illegal – for good reason.)