Buried in the Toronto Economic Bulletin
(warning: Excel document) is a column listing the number of passengers passing
through Pearson International Airport (YYZ) each month, going back more than
fifteen years. There’s a story to tell in the forecast, too:
Flight data are a great forecasting example because they display such clear
seasonal patterns, in this case peaking in the summer months and falling off in
the winter. R has excellent tools for working with time series data and whipping
up simple forecasts like this one. But there’s some friction with the modern
tidyverse tools, because the latter expect a data.frame
as the common
interchange format.
In this post, I’ll outline an approach to fitting many time series models using
the tidyverse tools, including model selection for out-of-sample performance. To
ease the transition between these two worlds I make extensive use of list
columns and the broom package.
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Last summer I landed a few patches
in Emacs’s ledger-mode
that make it easier to use with alternative
implementations of Ledger, such as hledger.
Since the competing hledger-mode
garnered some attention
last week on Hacker News, I
thought these new features might be worth highlighting to those interested in
plain-text accounting in Emacs.
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A few years ago I published a post outlining how to make nice-looking
choropleth maps in R,
and this piece still draws a reasonable share of my hits each month.
Unfortunately, some of the techniques I used at the time are now quite out of
date, and I was starting to feel bad for anyone taking my advice.
As of today the post has received a makeover, and takes a more modern approach.
For any returning readers, the changes are explained in a series of HTML <ins>
tags — which I have only recently discovered.
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Some time ago I discovered a very surprising performance issue while working
with the Rcpp
package, and
thought I’d share the example I discovered.
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If you’ve used the clocking features of org-mode
, you’re no doubt familiar
with the clock table, which
allows you to summarise time spent on different tasks. This is great for getting
an overview of projects, but it’s not a very flexible tool if you want to have a
more detailed idea of how you spend your time.
At this point I’ve accumulated about a year’s worth of clocked work time in org,
and while clock tables have served me well so far, eventually I just wanted to
get my data into R or Python for more minute analysis, and charts like the
following:
![Calendar heatmap example](/images/calendar-clock-heatmap.png)
However, I haven’t come across a reliable way to get individual clock entries
out of org-mode
files and into a more widely readable format. So I’ve written
one.
Continue Reading →