PHP


Scraping pencils 1

Pencils not only seem to be reliable writers, they also seem to be reliable in terms of keeping their prices affordable.

In June this year I used R to do some web scraping. The data collected was supposed to be for a follow up of my Why did stationery become so expensive? blog post. Well, this is the follow up blog post and there isn’t much to show, maybe because we are talking about wood cased pencils. Fountain pens and mechanical pencils had a more extreme price development.

I did the R code not only for the follow up, but also to teach myself a bit more R, I would have normally done this in PHP, which I am more failure with, having used it since the 90s and having used it for similar tasks in the past (even though people didn’t call these tasks web scraping at that time, or if they did I did’t know).

chart showing how the Koh-I-Noor PolyColor Art Pencil prices have changed.So what exactly did I do? I was looking at how the prices for pencils have changed on the Cultpens web site over time. My code that will get historic prices from archived versions of the Cult Pens pencil web page from archive.org is available at GitHub if you want to try it or change it for your own purposes. If you do please bear in mind that my code is not very good, I realise this, but as I am new to R I don’t know how to improve it (at the moment – I hope to find more time to learn R in the future). Also, if you try this please try to minimise any strain on the server you get your data from.

The findings were less exciting than expected. VAT has changed a few times over the last few years and there are obviously currency exchange rate fluctuations to be taken into account, as well as inflation and other factors.

The most interesting changes I could see was a > 10% price increase for some Graf von Faber-Castell products between 2010 and 2011.

The  Tomboy Mono 100 got cheaper over the years. Between 2010 and 2013 it got > 20% cheaper.

The most extreme price rise was for Koh-I-Noor products. At the beginning of 2014 the big Polycolor Art Pencil tin got nearly 40% more expensive, smaller tins got more expensive, too.

Overall prices seem remarkably stable.

As mentioned before I assume the price stability is also linked to this being pencils. As shown in my previous blog post fountain pens seem to attract more extreme price hikes.


Picture: Mongol plus Pilot Color Eno pencils on Brunnen Der Grüne Block.