Random variables demystified

A short post today, as I'm preparing for midterms. This video intrigued me; it's an introduction to random variables and the concept's well explained.



This YouTube link is from Khan Academy, a non-profit started by a former hedge fund analyst and Harvard MBA. I've not even scratched the surface of the offerings at their site or on their YouTube channel, but they appear to have a treasure trove of good stuff. I've added links to their site on the resource section to the right of the blog.

Persuasion through liking -- or at least acting that way

The public television station and public radio station here in Chicago occasionally team up to produce pieces for both audiences. I'm currently listening to one of them, "Chicago Matters: Money Talks," on my commute. It's a multi-piece series on the different ways money affects each aspect of our lives. The stories focus on Chicagoans, but the theme is pretty much universal.

One of the reports I listened to today was about tipping patterns of diners and how waitstaff view tipping and try to influence it. The reporter was also a waiter, and after interviewing Cornell professor Michael Lynn on tipping rationale and what things restaurant-goers respond positively to, he successfully increased the tips he received from diners. The tactics were simple, smiling, crouching near the table instead of standing over diners when speaking with them, and touching them while talking.

I reviewed my material from my leadership class after listening to this, especially "Harnessing the Science of Persuasion," by Robert B. Cialdini. One of six principles he says are critical to successful persuasion is liking. That is, developing an early, genuine feeling of goodwill toward someone and focusing on areas of similarity or areas where you think he or she merits praise. Their inclination to support you or do things for you should increase.

Lynn, the professor interviewed, said diners are paying bribes to waitstaff in order to feel that waitstaff like them. Both parties understand the charade, but want it to work. I'd prefer to limit my efforts at goodwill to those I think deserve it, but it's interesting to see that decidedly non-genuine efforts can also be effective. Lynn's got plenty of tips (advice, actually) for waitstaff at his site.

You can see a pared-down version of the article Cialdini published in BusinessWeek here if you don't have access to the full version in Harvard Business Review (it's available there for purchase).

You can find the Money Matters videos here at WTTW and the audio here at Chicago Public Radio.

Feedback and motivation

In my leadership course we just read "Motivation: A Diagnostic Approach," a chapter from Readings in Managerial Psychology. Nadler and Lawler lay out an "expectancy theory" approach to motivation, which holds that individuals' motivation is shaped both by individual and environmental forces. The three components driving motivation are: What outcome (good or bad) an employee thinks her performance will yield, what value she places on that outcome, and whether her abilities enable her to achieve the necessary performance.

Today at work I attended a seminar for supervisors that included a reading from a Harvard Business Review blog post by David Simms, Emerging Nonprofit Leaders: "More Feedback, Please."

Simms said that at a gathering of nonprofit sector leaders under the age of 40, most said they would probably leave their organizations eventually because of a lack of constructive feedback. I suspect that their attitude isn't unique to nonprofits, and it's easy to see the relationship between his observations and expectancy theory. If managers can't help employees learn how to get better, that erects barriers both to actual achievement and to what employees think is obtainable, both in terms of performance and outcomes. Even if you haven't read about expectancy theory, Simms' piece is worth a read.

Porter talks about the five forces

Nearly 30 years after his now classic 1979 article on forces that affect industry profitability, Harvard Business School's Michael Porter sat down for an interview about his update to that work, an article called: "The Five Competitive Forces That Shape Strategy."

We read that article in my strategy class last quarter and it was a great jumping off point for a lot of the concepts and cases that came later. Porter writes that "the five forces reveal why industry profitability is what it is." That's useful not only for analyzing current competitive advantage, but for looking at prospects for future success within that industry.

If you've read that article, you'll like watching Porter expand a little on these concepts during the interview. He goes over how all five forces combine to make the airline industry so difficult to profit in, while soft drink makers, on the other hand, have what he calls a "license to mint money." Harvard has a lot of great resources available for download or viewing, both on their site and on their YouTube channel.

What are the odds statistics can be funny?

I don't have time to read many books beyond what we're using in class. In fact, I'm lucky if I make it through all the assigned readings. That's why I'm on the lookout for podcasts of lectures or other material that I can fit into my commute or other times that I can't really study.

But I'll make an exception when it makes sense. Gonick and Woollcott's "The Cartoon Guide to Statistics" is worth the couple of hours I've spent to read the first half. I'll continue with it as my probability class goes on. Evidently it's practically a classic; I just stumbled onto it late. You can look at the table of contents and check out the reviews at Amazon, but it's probably in your library. Here's the link to the book's page at my library in Chicago.

Chapters five and six, on random variables and their distributions, helped me understand these dry topics a little better. The rundown on Bayes Theorem on pages 46-50 was particularly illustrative, though the multiplication rule was covered a little differently than it was in my class.

It's not that I've found information in this book that wasn't available in my class readings or notes, but I think the more ways you can sneak information into your head the better, even through comics.