Oil Changes, Gas Mileage, and my Unreliable Gut

Kia recommends that I get the oil in my 2009 Rio changed every 7,500 miles. But, anecdotally, it seemed that I always got better gas mileage right after an oil change than I did right before I was due for another one. So, I got to wondering - if an oil change costs $20, but saves me a few MPGs, is it cheaper overall to change my oil sooner than 7,500 miles? If so, where's the optimal point?

So, I got all ready to do some fancy math, and began tracking my gas mileage between two oil changes... And this is what I found:

gas mileage graph

This is why anecdotal evidence is unreliable.

At least based on this one oil change cycle, my gas mileage theory was 100% imagination. I should stick to oil changes at 7,500 mile intervals.

Of course, this is really a sample of only a single oil change cycle. It started in summer and went into winter, so winter fuel blends came out (which generally have slightly higher MPGs), and I presumably used the A/C less (though my defrost requires my A/C to be on, and I use the defrost a lot). There may be other complicating factors as well. So, I plan to track this all over again and re-visit after my next oil change cycle... because gut feelings die hard.

Analyzing the Billboard Hot 100 Archive

I recently downloaded the entire history of the Billboard Hot 100 chart, which has been tracking the most popular 100 US music tracks since 1958. So, I decided to see what I could learn!

Hot 100 Logo

Primary colors. Except not quite.

It only took me a couple of minutes to generate some interesting factoids. For instance, did you know…

  • That Rockin’ Around the Christmas Tree and Nat King Cole’s version of The Christmas Song both made it onto the charts for the first time in 1960… and both reappeared as recently as 2014?
  • Or that Imagine Dragon’s Radioactive spent more consecutive weeks on the chart than any song ever… at 85 weeks?
  • That the Beatles managed to have 14 songs on the Billboard Hot 100 at the same time in April of 1964? And that 5 of those songs managed to make the top 10 list simultaneously? Absolutely dominant.
  • How about that very few artists have managed to produce a #1 single, with no other charted songs… though the feat has been managed by Soulja Boy (with Crank That), Baauer (with Harlem Shake), and Daniel Powter (with Bad Day)? That’s the pinnacle of “one hit wonder” status right there.

Of course, a lot of these sorts of Hot 100 facts have already been calculated, so I decided to see what new information I could come up with!

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Scraping Grocery Store Ads for Fun and Profit

If we’re honest, I imagine most of us would admit we don’t really know what a good price is on the grocery items we purchase regularly. Except for a few high-priced favorites (e.g., ribeyes and salmon) that I watch for sales, I honestly have no idea what’s a regular price and what’s a good deal. How much does a box of raisin bran cost? Whatever the grocery store charges me…

harris teeter

A local Harris Teeter in my area. Usually, their prices are higher… except when they’re not. Honestly, I don’t really know.

Obviously, this is a really terrible way to manage my grocery budget – I probably spring for “deals” that are nothing of the sort all the time. So, as a data scientist, I got to thinking… what if I could keep tabs on this? Build a database of historic prices for various items, so I’d know when to pull the trigger on sales. Seems straightforward enough.

Well, I needed some data to get started. So, I figured I’d see if I could programmatically scrape prices out of the online weekly ad for my local Kroger store. In this post I’ll walk through how I got that set up… and, as this project moves along, I’ll post updates on what I do with the data.

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Data Show Stores Decorating for Christmas Earlier Each Year

Seems like every year around this time, I hear folks complaining that corporate America is decorating for Christmas way too early. Gone are the days when Christmas was reserved for December - now we're lucky to make it through Halloween without seeing wreaths and Christmas trees everywhere. But is any of it true? Are stores really decorating earlier than they used to? I decided to find out.

Of course, there's not really any available data on when stores around the country start decorating for Christmas (at least to my knowledge). So answering the question required some creativity. I started thinking - if there was one thing that represented corporate America's Christmas decorating traditions, what would it be? The Rockefeller Center Christmas Tree, of course!

Rockefeller Center Tree

The Christmas tree in Rockefeller Center.

First erected in 1933, the Rockefeller Center tree has been set up every year since and has become an unofficial start of the Christmas season for New Yorkers. And, since Rockefeller Center is without a doubt a bastion of American corporatism, the tree gives us a relatively good proxy for measuring the start of the corporate Christmas decorating season. If the tree at Rockefeller Center has been going up earlier every year, there's a good chance that's indicative of a larger national trend.

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Optimal Pass the Pigs Strategy (Part Two)

Still migrating old posts due to travel. Next post will be fresh content!

In a previous post, we learned that if you want to maximize your score on any individual turn of a game of "Pass the Pigs," you should always roll when there's less than 22.5 points in your hand, and hold when there's more than 22.5 points in your hand. (If you've never heard of "Pass the Pigs," the rules are explained in the prior post.)

I wouldn't mind being passed this pig for a few minutes... that's some serious cuteness right there.

However, we also concluded that that's not an effective strategy for winning the game as a whole. If you have a score of 0 and your opponent has a score of 99, for example, it would be really silly to stop rolling at 23 points just because the "22.5 rule" says to. So what's a person to do? How do you play effectively? Today, we'll generate a strategy that can help you make an optimal move in any situation. (Hint: you'll need to do a lot of math.)

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Optimal Pass the Pigs Strategy (Part One)

Since I'm out of town for a bit, I'm migrating over a few relevant posts from an old blog of mine that I'm planning to shut down. Enjoy!

Pass the Pigs is a simple yet addictive dice game that uses cute little plastic pigs as dice. If you've never played, the rules are very straightforward. On each turn, a player rolls two pigs. The pigs will land in different positions, which will determine how many points the player has in their hand for that turn. The player may then decide to "pass the pigs" to the next player. If they do this, all of the points in their hand will be added to their official score. They may also decide to roll the pigs again to try to add more points to their hand before passing the pigs. But they must be careful! If the pigs both land on their sides with one showing a dot and the other showing a blank side, they "pig out" and lose all of the points they've accumulated in their hand! It's risky business. The first player to accumulate a score of 100 or higher wins.

Pass the Pigs

Credit: Larry Moore

Like anything with dice (even pig-shaped dice), Pass the Pigs is a game of chance. That means, with a little effort, we should be able to figure out the probabilities of certain things happening in the game, and develop some optimal strategies. So how do you win at Pass the Pigs? Read on to find out.

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