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Making the Experiment Work

Once, back in grad school, I was talking to my thesis adviser about a particularly difficult experiment I was trying to figure out how to do. I was coming off an experiment run that took about two weeks from the start until I got the results back for analysis:

"It didn't work." I told her.
"What do you mean, 'It didn't work'?" She asked.
"Something about the way the experiment was run was wrong. I got no signal, not even for the standard curve and the controls. It didn't work."
"The only failed experiment is one you don't learn anything from." She chided me. "If you can't use this experience to figure out why it didn't work - or even to learn how you might figure that out with the next experiment - then you're just wasting time and money, hoping to learn something by random chance."

This is a powerful lesson, and one I want to expand on more generally. It's a lesson that should influence how we v…

Are COVID-19 cases already on the decline?

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Caveat: I am not an epidemiologist.  My fields are oncology, immunology, and to a lesser extent microbiology.  This whole situation is changing rapidly anyway, so uncertainty reigns during times like these.  I'm more interested in data analysis than I am in diagnosing conditions on the ground.

We should be careful - suspicious even - when we see data and think it's talking to us.  Especially in times like these, I often hear people say they're not doing anything fancy, they "just look at what the data say."  That's false.  Data don't say anything.  People say things about data.  Sometimes data can look very convincing, but then as you ask more questions and look at the data in a different way you can come away with different interpretations.  That's not what people mean when they say thy're just looking at what the data say.

By all means look at the data, but remember that if you're hearing something it's not because the data are talking t…

Covid-19: Epidemiology is useful

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I pulled this data from Google Trends of searches for "coronavirus".  I had to set a range that excluded everything from mid-December 2019 to the present, because they dwarfed all the other searches and compressed the scale.



As you can see, there's a natural die-off of coronavirus-related searches by mid-March, which is good news for those concerned with the present crisis.  I've heard a lot of speculation about the current coronavirus, Covid-19, and I want to talk about a few ideas from epidemiology to get at more general principles.  First, the reproduction number (R0) of Covid-19 looks like it's about 2.2.  Meaning each infected person is likely to infect 2.2 additional people before they clear the virus or die and are no longer infectious.  That means it's likely to spread quickly - or more accurately exponentially.

In fact, given an R0 of that magnitude, it's unlikely we'll be able to stop it from spreading, no matter how good our quarantine is. …

Nutrition Graph: Cereal Comparisons

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An old friend told me about a conversation he had with his daughter over breakfast, where they mused about which cereal has the most sugar.  That led him to create a simple diagram comparing about a dozen different cereals against their sugar content.  While I was reviewing his graph, I noticed it had a few major design limitations.  The most glaring was that he used the serving sizes listed on the cereal boxes.  I decided to make my own comparison graph, using weight and percentages by weight instead of measurements by volume.  This led to many more comparisons, and was part of the inspiration for my recent book.  The first graph below is the result for different cereals, sorted in order of most to least amount of sugar.



As I was looking at this graph, I thought about how sugar and carbohydrates are basically the same thing.  (A carbohydrate is just a bunch of sugars chained together.  The body breaks these down into their component sugars and moves on from there.  There's more o…

About Non-Empirical 'Science'

I appreciate reading content from people whose views are unique, but whom I disagree with a healthy percentage of the time.  The unique part is important, because if you're saying the same thing I can get a hundred other places I know you're not putting much individual thought into the message.  This is perhaps part of why I've never signed on - even nominally - to any of the major political movements or parties.  If one of them had all the answers, it feels like they would be dominant by now.  Not because everyone 'saw the light', but because if an idea works in practice more people do it, until everyone is doing it.

I imagine there are reasons this wouldn't be the case.  For example, both major parties in the USA often claim that their reforms/policies 'would have worked if it hadn't been for those meddling people from the other party'.  And while that's an unfalsifiable claim that might well be correct, it doesn't really help convince me …

Back in the Day

Today's subject is about a problem I see often enough that I'm certain I've been guilty of it myself in the past, and will probably be guilty of in the future as well.  In fact, if you see me doing it feel free to call me out and link to this post.  I'm not shy about being wrong.  I've had a lot of practice at it.

The issue became apparent to me recently while reading a book whose author I'll not shame.  It was a kind of self-help book, which attempted to explain  ways to overcome normal human behaviors in order to make it easier to be happy (which is incidentally about the most generic explanation for a self-help book I can think of).  While explaining their shortcuts/insights into human behavior, the author explained that the reasons for the normal, maladaptive, human behaviors they were trying to correct all lie in evolutionary history.  You see, humans back on the savannas of Africa in hunter-gatherer societies were bad at [insert perceived failing of human…

New Book Live! - Nutrition Intuitions

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As promised in a previous post, I finished - and published - my book on nutrition in time for the new year.  The focus of this book wasn't about how much of which vitamins and minerals you should get, or what each thing does in your body.  There are already plenty of books cataloging that kind of thing, and I'm not certain they're useful anyway.

My aim in this book was to build intuitions for the non-biologist about how the body works and what to expect from the body.  Faithful readers of this blog will notice a few chapters were pulled from previous posts, though with some editing and modifications.  Even so, most of the book is new content, including a few chapters of data that are - to my mind - a lot of fun to read and reference.

The problem I've always had with the nutrition labels on all my food is that the information is presented to me as though it's meaningful.  Everyone pretends it's meaningful.  It's even formatted to look like it contains seriou…