A Science for Everyone

Mass Shootings and Jumping to Conclusions

I noticed reports of a supermarket shooting in Colorado – at first the perp was a white supremacist, then an ISIS influenced domestic terrorist, and, most recently a Syrian-born immigrant with mental health issues.  There’s a challenge when you need to get a story into print quickly, and the first story often changes.

Mass shootings have been a topic for research, and data is available online.  I’ll refer to  Emma Friden’s study in the Journal of Interpersonal Violence – it can be accessed at here.


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Excerpts show some of the challenges in dealing with the topic.  Friden begins by separating these into 3 categories- familial, public and felony. 

The public area mass shootings are what we tend to think of most frequently, but her chart shows that the most common mass shootings are familial, when someone loses it and murders their family.  Felony mass shootings refer to the shootings that occur during a felony, often to get rid of witnesses.  Her descriptive statistics are below.

Sometimes the interesting part of the statistics is what isn’t there – in this case, there is no category for sex of the offender.  I’m not certain, but I suspect it’s all male in the data set. 

The second set of numbers that set off a mental bell was for immigrant offenders.  It seems disproportionately high – though I’ll need to use Census data to check.  I like seeing data – it makes things much more understandable.

I can’t make a good excerpt of the paragraph that sums up her work, so I’ll ask you to read the whole thing: “These findings are broadly consistent with prior research, as familicides are primarily differentiated by victim characteristics, felony killings by offender characteristics, and public massacres by incident characteristics. Specifically, offender and victim characteristics distinguish family from felony murder; victim and incident characteristics distinguish family from public killings; and offender and incident characteristics distinguish felony from public massacres. However, only a few traits consistently differentiate each type from all others: Family killers target children and other family members of the same race, felony offenders rarely perish after their crimes, and public attackers use guns to injure as many victims as possible. More interesting than these anticipated differences among the three groups are the traits that do not significantly vary, contrary to traditional assumptions. Although previous studies have suggested that family killers are older than their counterparts, suffer from financial stressors, and tend to target more female victims, none of these predictors could significantly differentiate familicide from the other two types when all other variables were accounted for in the model. Similarly, felony killers are no more likely to be Black over White in comparison with family killers, and no more likely to have a violent criminal record than either of the other categories. Far from mentally ill pseudo-commandos, public killers were just as likely to have been treated for mental illness or have military experience as other assailants.”

Usually, criminology isn’t my thing – generally, crime is defined socially and is kind of a moving target.  I’ve watched marijuana go from felony to legal, varying by time and state line.  This study deals with something that is consistently considered a crime, and categories that are definitive.  Her article is definitely worth reading.

A Science for Everyone, Meteorology

Windchill

It’s not really that cold out, is it?

Are you asking the thermometer? To a chemist or a physicist, temperature is really just a measure of how fast the molecules that make up air are moving, how much energy they have.

To those of us more interested in what the thermometer says outside, temperature has more to do with the rate at which we exchange heat with the environment. At the same temperature, a metal spoon will feel hotter than a wooden one; The metal spoon, being metal and thus more conductive exchanges heat with us at a faster rate, and so feels hotter.

Cold works the same way. The faster we lose heat, the colder it feels, even if the reading on the thermometer hasn’t gone down any.

Windchill, then, has to do with the way wind changes the rate at which we exchange heat with the air around us, specifically the rate at which we lose heat.

It makes an obvious sort of sense. The more wind, the more particles of air move by us, the more opportunities for particles of air to get a little warmer and us to get a little colder. But it’s actually worse. Wind will strip away that nice little layer of air you’ve already exchanged some heat with. It’s slightly warmer (which means its taking slightly less of your heat) and keeping all that really cold air from touching your skin. Insulating. Wind strips away that insulating layer of air.

Windchill, while ostensibly a measure of how cold it feels, is really a measure of heat loss. At it turns out, your body cares far more about how cold it feels than how cold the thermometer reads. While your skin temperature isn’t going to drop below ambient temperature, your body will perceive things as colder than they are, and respond accordingly. Frostbite? Hypothermia? The symptoms of those are the result of the body responding to how cold it feels.

Thirty degrees and windy can’t actually drop your skin’s temperature below thirty, but it’ll feel colder, and that is enough to increase the risk of cold related injury such as frostbite. While the equations to calculate windchill vary a bit, windchill warnings are serious business.

It’s not really that cold out, is it? Not if you ask the thermometer. If you’re asking me, however…

A Science for Everyone

Inflation

Inflation is one of the very basic, very important economic concepts. It is deceptively simple. Increase the supply of money, and it’s like inflating a balloon. The amount of air in the balloon increases, the amount of money in the system increases. This is essentially what happens whenever the government prints more money.

When the amount increases, the value of each individual unit goes down. This becomes more difficult to understand, because a dollar is still a dollar. However, a dollar doesn’t purchase as much.

Think back. Remember. How much was gasoline ten years ago? Twenty? Thirty? But it’s not always the price that increases. Sometimes, the amount goes down. Candy-bars, anyone? They’ve shrunk considerably since I was a child admiring them in the checkout isle. Of course, some things increase in efficiency and decrease in price, even while others do the opposite. Why? Developing technology can really reduce the costs of making something, sometimes enough that the price declines, even as the value of money goes down.

The federal reserve aims for an inflation rate of 2%. But that’s a number with very little meaning to most people. We care more about how much the grocery bill will increase by. For that, we look at the consumer price index. Calculating how much the value of money has changed is as simple as having two reference points. Pick an item. What does it cost today? What did it cost back then? Do a little subtraction, and then a little division.

Of course, you could also use the CPI inflation calculator provided by the government. In that case, it told me that a 100$ in 1920 had the same purchasing power as $1,342.65 in 2020.

Why do we care about inflation? Sure, groceries cost more, gas costs more, electricity costs more, but we’re earning more too, right? Eventually, probably. What’s really concerning is when inflation is high, when you see the kind of chance the US dollar had from 1920 to 2020 over the course of a year. Wages just can’t keep up.

Literally printing more money, while the obvious (and easiest) means of causing inflation, isn’t the only way to go about it, but the alternatives are a bit complex for this summary.

A Science for Everyone, Meteorology

Measuring Wind Speed

While it’s certainly possible to measure wind speed with an anemometer, looking out the window is often good enough.

That’s because, back in 1805 Admiral Sir Francis Beaufort developed this handy scale for guessing wind speed based on the sort of observations that can be made out a window. As windspeeds increase, Beaufort’s scale starts to look positively superior to an anemometer. With my little handheld anemometer, I have to go stand out in the weather and hold it. Beaufort’s scale? I can make my estimate from the inside, a decided virtue.

beaufort
This is probably one of my favorite charts for determining wind speed, but I haven’t found its origins yet.

While Beaufort’s scale isn’t going to be useful in all situations (a still summer’s day, when no fires are burning, for example), it’s still pretty handy. And, the times its most useful coincide nicely with the times I’d rather be indoors watching the storm instead of standing in it.

According to Beaufort’s scale, that little whirlwind we had last fall, having caused some structural damage, was probably somewhere between 55 and 60 miles per hour.

With roofing torn off, the wind was definitely more than a “Fresh Gale: Twigs and Small Branches broken off trees”. The next level, a “Strong Gale” has slates blown from roofs. While I’m no expert on roofing, the damage seems to be a bit worse than that. So, probably in the “Whole Gale”, or 55-60 range.

In that instance, using Beaufort’s scale seems far safer than standing outside with an anemometer, even if the machine would be more precise.

Community

Snow Pack on the light side of average

45 years ago, it took a week’s effort on a Ski-doo Alpine to get the data I can download in 10 minutes. We were high-tech then – two tracks and a single ski on each snow machine, and clockwork powering the recorders that kept track of the water equivalent setting on the snow pillow. Now there are fewer stations – and the missing Bald Eagle Peak data reminds me of the winter climbs up the mountain, carrying the heavy sampling tubes, on snowshoes. Probably the hardest work of all, and that data collection no longer maintained.

The simple description of the snowpack is that it is a bit lower than average, but next month will provide enough data for the NRCS hydrologist to start projecting data. We always tried to have the measurements done for the first of the month, so I looked on January 31. The ten-minute download from the places I once spent the better part of a week getting to is:

Water EquivalentPercent of Average
Banfield Mountain10.4 inches87%
Hawkins Lake15.5 inches96%
Garver Creek 7.1 inches103%
Stahl Peak20.7 inches89%
Grave Creek8.6 inches81%
Poorman Creek17.1 inches75%
Bear Mountain30.2 inches82%
Hand Creek6.0 inches81%
Noisy Basin23.0 inches90%

To get to the data – and the map – you just click https://www.nwrfc.noaa.gov/snow/ .  It also provides elevations of the sites so you can get a great idea of how the winter snow is up high.  Making the data so readily available makes hydrology a science for everyone.