This marching band keeps walking around the block and there's not even a parade

She used her grandma's recipe for the cakes

The concept of "expected value" is a tool to predict the outcome value of some situation by looking at each possible outcome value and how likely it is to occur. For example, if choice A has a 25% chance of earning you $100 and choice B has a 10% chance of earning you $1000, you might say that A has an expected value of $25 and B has an expected value of $100. An EV is useful as a tool to think about decisions, but unless the scenario is going to be run over and over again (enough times that the math starts to show up) it's not going to be predictive of one single run.

There were articles in the news recently where the total value of the Powerball lottery got high enough that it had a positive expected value (which is atypical, this is usually a negative number). What's really being said there is that for every $1 spent on the lottery, ticket purchasers on average will receive more than $1 back. Of course the reality here is that 1 or 2 people are going to have an incredibly positive return, and tens of millions of people are going to have a return of zero.

Have you ever looked at statistics about who buys lottery tickets and how the whole thing works? It's not good! Yikes. That's not the point here.

Anyway, I wonder what the Expected Value of "A high school student writes a song about love while they are learning to play the guitar" is. There are about 15 million high school students in the US in a given year. Using some internet data that for all I know is just totally made up, I've learned that just under half of high school students play some instrument, that males are more likely than females to play the guitar, and that about 13% of the US population can play the guitar.

I have no idea if this is high or low, but it's what we have and this newsletter is not about to start striving for statistical rigor. Let's just assume that of those 15 million students, that 1.5 million of them are playing the guitar. Of those, probably 150,000 are writing love songs and attempting to perform them for their friends. In a given year let's say there are 100 songs of the "wow, that was a guitar song about love and it's existence probably just changed your life in an economically interesting way" variety, and that the entirety of these songs are emerging from the recently-in-high-school demographic.

Let's say that one million (million with an M) dollars is life-changing, and 100/150,000 = 0.0006666666... we multiply that by the cool million -- and that all means that writing a song about love in high school is worth about $666. THE NUMBER OF THE BEAST!

Pulling the 'chute

As revealed in previous newsletters, I'm not the sort of person who regularly weighs himself, but I am the sort of person who will not miss an opportunity to step on a scale if I happen to be somewhere that has a scale. This "keeps me honest" or whatever.

One nice side effect of knowing roughly but not exactly what you weigh is that when you're out on the road in a new city staying in a hotel or staying at a friend's house, you are primed to help them calibrate their scales in a way that's not very exact and doesn't really get you anywhere.

If you weigh somewhere in the 77-80kg range on your own home scale, you might consider this a normal range for your weight to bounce around, and be comfortable with this week to week fluctuation. When you're at a friend's house, if you use their scale, and their scale shows somewhere in the 75-82 range, you can probably consider their scale to be calibrated closely enough to yours that you are still in your typical range. But, if their scale shows anything under about 74 or over about 83, you might want to come downstairs for breakfast one day and say "hey buddy I think your scale is a little off".

Make sure you're polite about this because your friend might have an unhealthy obsession with their weight, or with the precision of their scale.