Tuesday, August 28, 2012

Hire the Uglier Model, Part 2

An earlier post, Hire the Uglier Model, encouraged evaluation of two similar job candidates by choosing which one had more to overcome. Hiring managers typically take the opposite tack and select the candidate with more accolades. One way to think about this is with some basic geometry:

A candidate's status can be thought of as dependent upon how fast he develops, how many years he's had to develop, and how much of a headstart he had in life. This can be written as follows:

Development_Status = Development_Rate x Time + Headstart

If you think of this as a line equation ( y = mx + b ), then you can plot the respective lines of two candidates and make an estimate of future success. I'll use some unspecified units for both Development Status and Time (all that matters is the relationship between the two candidate's values, not the units per se).

So take two candidates, each with the same Development Status after 25 Time units have elapsed. They have equal Status right now. However big candidate A's headstart was, it must have been offset by candidate B's superior Development Rate. Since you are hiring based on expected future prowess, candidate B is more likely to exhibit this since he has overcome B's headstart hurdle and has now leveled the playing field, ready to leave B in the dust. Yes, there are other factors to consider (diminishing returns, non-linearity, etc.), but B is a better pick, ceteris paribus.

There is evidence that some top firms have figured this out. Lara Stone is on Vogue covers; Stacy Keibler is not.

Thursday, August 23, 2012

Now Hiring Amish Database Administrators, Inquire Within

Priest / Referee / Judge
No surprise that a candidate's morality is a crucial component to hiring someone for these jobs. But what about a database administrator?

Think about delivering business intelligence from a data warehouse as an assembly line:

  1. Query the database for the raw records
  2. Analyze the records
  3. Create report from the analysis
  4. Create action plan from the report
If you want to know what exactly happened during step 2, you could compare the changes from steps 1 and 3 to see what's different. Same with knowing what step 3 entailed. Comparing step 3 to the final product lets you see what went on during step 4. The ONLY step without transparency is step 1. That's where integrity comes in. Unless you plan a major project to test whether your database administrator is displaying honesty and competency, the best solution is to hire one with good morals*.

No post-modern DBAs need apply.

*What are good morals? From the film K-Pax:Dr. Mark Powell:  How do you know right from wrong?
Prot:  Every being in the universe knows right from wrong, Mark.

Monday, August 13, 2012

Would you brush all but one tooth just to know how much brushing has helped?

Thou Shalt Have a Control Group is a popular refrain in analytics. But is a controlled experiment always worth it?

As William Coyne said, "[A]fter you plant a seed in the ground, you don't dig it up every week to see how it is doing."

You may want to spend an amount of money optimally, but you have a control group designed not to do anything differently. That control group has some elements that you would want to spend money on. This lends itself to a modified Heisenberg uncertainty principle:  you cannot optimize and be sure you have optimized simultaneously. Or more familiarly:  if you're the best, you'll never know it. A setback for narcissists.

What's 20120768 minus 20120755? Weakness.

A firm's leverage with a supplier is often based on how much of the supplier's revenue pie the firm represents. This leverage can express itself in ways such as bargaining power and prioritization.

Since this leverage comes from the point of view of the supplier, the firm may not directly know its relative importance. One proxy is to look at the invoice numbers that the supplier sends you. If the numbering scheme appears sequential then you have an idea of how many other invoices the supplier has sent out since your last invoice. Conversely, a shrewd supplier should obscure its invoice numbering scheme to minimize this leak.

The Message is the Medium

Shaq knows.
Why should you read?

Does the medium really matter? Is the written medium better than other media?

When you hear others talk, you are likely hearing their average thoughts (or within a reasonable range of average). When you read others' writings, you are often hearing their best thoughts (or what they believe them to be).

So reading may not be important per se; however, it is a strong indicator that the underlying content is much stronger.

Listen to me.

Thursday, August 9, 2012


Tika-Taka. That's the name of F.C Barcelona and Spain's soccer teams' style of play. Essentially, it means playing keep-away for long stretches of time until the opponent gets out of defensive position (often from frustration or fatigue from chasing the ball). It would be hard to argue that these teams aren't excelling with this style:  both have won nearly every trophy available over the last few years.

But are they playing optimally? Could they be even better?

A digression. Elite basketball coaches in the U.S. have adopted a mindset whereby they look at statistics on a per-possession basis. Maybe your team has been scoring 1.1 points per offensive possession, while your opponent has been scoring 0.9. You're a better team, assuming similar prior competition. The only problem is that these are just the averages. On any given set of plays, there could be a wide variation...someone banks in a bad three-pointer, etc. But as more and more possessions take place, these blips should wash out to the 0.9 and 1.1 averages. So each team's strategies suggest themselves:  the better team wants lots of possessions; the other team wants fewer possessions. "Possessions" mean trips down the court, not time with the ball.

Back to the beautiful game. Soccer strategy can change dramatically once the first goal is made, since a lesser team can often set up shop on defense knowing it is not necessary to score again (maybe). But for the aim of scoring the first goal, soccer's analog to # of possessions is # of times the ball is within, say, 25 yards of the goal. In this case, the superior team would want to create as many chances as possible. To do so, the players must minimize the time spent doing unproductive things. Even thirty extra seconds could lead to one more opportunity that notches a goal.

Of course, the method in which the ball reaches 25 yards of goal matters. If your per-possession stats are based on quality approaches then that's what you'll need to continue doing. Wasted time can be shaved off during restarts, limiting back-and-forth kicks among the fullbacks, winning turnovers as high up the field as possible, etc. Playing faster is another option; so is adding players with good long-range shooting to extend the 25 yard zone. A team can even make a trade-off if rushing an attack hurts its chance of scoring by 8% but it gets to try 10% more often.

The better team will go high-pressure defensively and minimize wasted time to attack as often as possible while the underdog is still trying to balance out offensive and defensive priorities.After scoring a goal, the team can sink back into playing keep-away to reduce the number of opportunities for the opponent.