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The Big Two – They’ll Be Back

December 10th, 2010 bclark No comments

After this year’s Ohio State-Michigan game (37-7), Ohio State coach Jim Tressel offered a statement that I never expected a Buckeye coach to say. “Michigan will be back. You don’t have to worry about that.” While some Big Ten fans (and even Buckeye fans) make comments about how recent lopsided runs have diluted the rivalry, I’m in no particular hurry to see Michigan return to the top of the conference standings.

But Tressel’s comment got me thinking about a fact I’d read once years before. A decent chunk of the wins that make Michigan’s football program the winningest in the country came in the first half of the 20th Century. If college football has changed since the days of Woody and Bo, it has definitely changed since the time of Fielding Yost.

College programs and conference strength is cyclical so I don’t doubt that Tressel’s statement was true. But I wondered how Ohio State and Michigan have fared over the life of their programs.A chart showing the winning percentages of Ohio State and Michigan

Michigan is clearly dominant early in its history, and it went through several down periods in the 1930s and 1960s before its current troubles. Meanwhile, Ohio State seems to vary much more. Its record is more spiky. When the Buckeyes are good, they’re good. And when they’re down, they’re down. But the only time they’ve fallen as low as Michigan in the past 100 years was during the 1940s.

This left me with one further question. How do the teams look when compared to the entire Big Ten conference?

I grabbed the season winning percentages for the 11 teams currently in the Big Ten since they began football. I wasn’t trying to capture the time since the school joined the conference. I wanted to look at how dominant the programs were overall – even if they didn’t line up against each other every year. Finally, I added a 10-year moving average for Ohio State and Michigan.

While other conference teams have surpassed one (or both teams) for a year or two at different times, the moving average is clearly well above the normal season for the bulk of the Big Ten. It’s normal for the single best team in the Big Ten in any given year to keep pace with the 10-year average for the better of these two teams. I was really surprised to see just how dominant the two programs are. One team or the other is always at the top – if not both teams.

A chart showing the winning percentages of all Big Ten teams.

The other big thing I learned from my two weeks of number crunching? Tressel’s comment was a bit off base. Michigan’s 10-year average still has two 10-3 seasons (2002 and 2003) and an 11-2 season (2006). But it’s only recently began to drop its moving average and is only slightly below the period of the early 1990s that would include the Earle Bruce-John Cooper transition years in the Buckeyes 10-year average.

Categories: Analysis, Tangents

Grilling Time

August 22nd, 2009 bclark No comments

Last year, we borrowed my father-in-law’s second grill. We put it to use and ended up grilling more than 60 times during the year. This year, we set out to grill out at least 72 times.

The only dry part of the Memorial Weekend cook-out was the grill lighting.

The only dry part of the Memorial Weekend cook-out was the grill lighting.

This summer has been particularly moist. It’s been cloudy and wet – half the days in July had rain. But my wife and I have done a good job sneaking in meals at the grill. It’s been a few more lunches than expected (and even breakfast one time). Our big Memorial Day bash was drenched – the out-of-town guests still said they had fun. We’ve dodged rain drops to grill and to pick and choose the days and meals we cook outside.

Earlier today, we grilled out for the 60th time this year. We’ve done the classics – burgers and hot dogs, steak, and chicken. We’ve grilled brats, salmon, tilapia, and pork chops. We’ve even grilled bacon and sausage (but not the famous explosion). And we’ve grilled countless vegetables as sides to almost all of these meals.

Summer is winding down. Fall weather is great – but it isn’t always the best for grilling. Grad classes start a little more than a week from now. That will bring shifts in our work and responsibilities. My wife and I have a busy few months planned – organizing and combining books and movies, scanning photographs, wrestling with boxes of files from one of the community groups I’m involved with. There’s also a handful of weekend trips – weddings and orchard visits among them – scheduled.

Here’s looking forward to at least a dozen more times over the grill.

Categories: Tangents

Summer Heat? Time to Dial Down the Energy Usage

August 13th, 2009 bclark No comments

During a road trip this past Friday, I grabbed a magazine from the unread pile to catch up on some reading. Turns out my Outside subscription has expired. (I’ll get a renewal/resubscribe in after getting my next check – or I’ll go back to reading it online.) And it turns out I was way behind on my reading. The issue I grabbed was September 2008, which was great – it had an article that coincided nicely with the Hot, Flat, and Crowded book that I had read.

The article is the written exchange of two of the magazine’s editors in a competition to track their energy use. I had downloaded my electric bill about a month earlier, and I decided to join in the comparison a year late (and without the technological gadget). Without the special software, I would only be able to estimate my daily use. That’s still good enough for me to begin to understand how much power my wife and I use compared to other households.

First, I checked out PPL’s website, which lets consumers access special tools to understand their electricity use. I downloaded the account history and looked at the kilowatts used. Big increases in the winter months and valleys in the summer. Our rented half-double has no insulation (we’ve bugged the landlord about it to no avail – and without much opportunity to look for other options). That means the heating unit uses plenty of electricity trying to keep the old house warm during the cold winters. We topped out at 693 kilowatts in February 2008 – before we began dialing the thermostat way down during the day. Our best full month was July 2007 when we used 336 kilowatts.

An easy spreadsheet formula gave me the number of days in each billing period. From there, it was easy to track the average kilowatts per day. The Outside article (if you didn’t follow the link) says the average American household uses 30.25 kWh per day. The most we used was 23.1 kilowatts in February 2008, and our best month was 10.5 kilowatts in July 2007. The two competing editors fell between about 8 and 18 kilowatts. I have some work to stay in their league. My median was 14.86 kWh, and the mean was 15.28 kWh. There aren’t big fluctuations in our energy use except for a few key months when it really spikes.

Average daily electricity use

Average daily electricity use

I wondered what the trend was from year to year. I took a few minutes to reconfigure the chart to map out the monthly use over the course of 2007, 2008, and 2009 – and I checked the mean for each of the 12 months. So far in 2009, we’ve been below the monthly average every month except for January.

Average Daily kWh by Month

I’ve actually followed the average pretty closely for most of this year. August heat and air conditioners have driven up our electricity in the past – that’s something we haven’t done this year with a cooler summer. Look like the windows are staying open this year, and I’m looking for ideas on how to winterize.

Categories: Analysis, Tangents

Tracking Climate Change In My Own Backyard

May 30th, 2009 bclark No comments

I’ve been reading Hot, Flat, and Crowded by Tom Friedman. He argues that demographics and globalization risk making climate change more dramatic than earlier projected. He also expands climate change to be more than Global Warming. He terms it “Global Weirding” and writes that the impact varies from place to place. Some areas have higher temperatures while others have colder weather. Certain months are impacted more than others. Sometimes the result is more rain – other places report dryer conditions.

But global warming is how everyone thinks of climate change so Friedman writes about a series of interviews where his subjects talk about noticing warmer weather. Western ranchers talk about less snow remaining on mountain tops. Another person speaks about the number of record highs and lows set across the country each week. That left me wondering whether I could find any change in weather in my area simply by looking at record highs and lows and when they were set.

I checked the National Weather Service’s repository of record highs and lows for the Scranton/Wilkes-Barre area – my current home. I used the tables from 1955 to present because they’re pulled from a consistent place (the airport) rather than the general area. I typed the date, record high (“maximum high”) and corresponding year, and record low (“minimum low”) and corresponding year into an Excel spreadsheet. It’s unfortunate that the records only cover 54 years, but they’re taken from a consistent area, which was more important to me than whether they covered 100 years worth of temperatures.

Because I wasn’t counting leap day, I had 365 days. The time period covered 54 years. Simple math says that if there are 365 record highs and 365 record lows, I should be able to expect about 7 record highs and 7 record lows each year.

If this covered two years – 1955 and 1956 – I’d expect half of the highs to be from 1955 and the other half to be from 1956. If it covered five years – 1955 to 1959, I’d expect 20 percent of the highs (73) to come from each year. Because I have 54 years, I expected 1.85 percent of the highs to have occurred in any one year. In a 365-day year, that’s 6.75 days. There were 365 lows as well – one for each day of the year. Odds say that another 6.75 lows – rounded to 7 – would set records each year.

I realize that some years just happen to be warmer or cooler than others, and so I wanted a way to lump years together. I decided to do it by decade. There were five years in the 1950s, nine years in the 2000s (the chart doesn’t cover 2009 temperatures), and 10 years for the 1960s, 1970s, 1980s, and 1990s. So odds say that I should have 33 or 34 records from the 1950s, 60 or 61 records from the 200s and 67 or 68 records for the other decades. If my numbers were around there, we’d be setting roughly equal numbers of record highs and record lows each year – and you wouldn’t be able to track the weather getting warmer or colder.

I didn’t get those results.

Decade Projected Number of Records Number of Record Highs Number of Record Lows
1950s 33.8 20 56
1960s 67.6 55 76
1970s 67.6 51 76
1980s 67.6 63 58
1990s 67.6 96 54
2000s 60.8 80 45
Total 365 365 365

As you can see, there were a lot more record high temperatures set more recently than record lows. In the 1990s and the 2000s, there were 77.8 percent more record highs set than record lows set. We were still setting record low temperatures, but we were setting new high temperatures much more often. While the 1990s represented 18.5 percent of the years in the study, 26 percent of the high temperatures occurred in that decade. The 2000s represented 16.7 percent of the years, and 21.9 percent of the high temperatures. The 1950s are 9.3 percent of the years in the study, and 5.5 percent of the high temperatures. That same decade has 15.3 percent of the record lows for the period.

We’re setting both new highs and new lows in each decade. But there highs are coming more frequently most recently. But how drastic is the change? It’s difficult to see because the 1950s and 2000s don’t have the same number of years included as the other decades. To have a better view of the trend, I divided the 54 years into nine groups of six years each: 1955-1960, 1961-1966, 1967-1972, 1973-1978, 1979-1984, 1985-1990, 1991-1996, 1997-2002, 2003-2008.

Odds should say that you should have roughly equal number of record highs and record lows set in each time period – just more than 40.5 each. (1.85 percent of the highs in each of the six years is 11.1 percent of the records, and 11.1 percent of the 365 days in a year is 40.5.) The final numbers didn’t match the odds. Remember, the number of records for both highs and lows should be right around 40.

Number of Records Set

I’ve been really surprised to see this result. I’ll take some time to look into individual months to see if any part of the year is more affected than another. But it turns out to have been pretty easy to chart the fact that’s it’s getting warmer in Northeastern Pennsylvania. We’re setting many more record highs than record lows.

Categories: Analysis, Tangents