• L1 regression solved six ways

    The most fundamental technique in statistical learning is ordinary least squares (OLS) regression. If we have a vector of observations \(y\) and a matrix of features associated with each observation \(X\), then we assume the observations are a linear function of the features plus some (iid) random noise, \(\epsilon\):

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  • Coronavirus lockdown: balanced on a knife edge

    Countries around the world are going into more-or-less complete states of lockdown in an effort to stop the spread of novel coronavirus. The question I find myself asking is whether the obvious economic cost of this can possibly justify the benefits. I built a model to answer this question and I find that, contrary to my priors, lockdown is actually justifiable under reasonable assumptions.

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  • Predicting international house prices

    What factors influence house prices? This is a perennial topic of dinner party discussion, but the standard of the debate rarely rises above offering anecdotal evidence. Frustrated with the status quo, I decided to tackle the question with statistics. In this post I look at which macroeconomic factors are associated with future house price rises or falls.

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  • Is Bitcoin a junk asset?

    One reason to believe that Bitcoin is a poor investment is because it is a rather volatile asset. As a general rule, “lottery like” assets with high variance in their valuations are known to underperform low-risk equivalents:

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  • Do children make you happy?

    Do children make you happy? This is a question that anyone who is considering starting a family should be asking themselves. Among my peers there is a widespread assumption that children are a key ingredient in a happy middle age, but it’s never been clear to me that this is so.

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