Following on from my post on Visualizing the Hottest 100, I noticed that the UK’s Guardian newspaper has published a list of 1000 songs to hear before you die*. The list was assembled from nominations posted by readers. Even before looking at the list, I suspected that the demographic profile of the Guardian’s readers may be a little different to that of Triple J’s listeners. A look at the distribution of year of release in the two lists bears that out.

Year of Release “Five Number” Statistics

In fact, fully 14% of the tracks in the Guardian’s list were released before the earliest track in the Hottest 100. Interestingly, that track was Bob Dylan’s “Like A Rolling Stone”, which also features in the Guardian’s list.

While the 1000 songs are not presented in any particular rank order, they are grouped by “theme”. The themes are heartbreak, life and death, love, party sonds, people and places, politics and protest and, of course, sex. This allows us to investigate the evolution over time of these different themes.

The chart below is a “box and whisker plot”, also known more prosaically as a “box plot”. It provides a graphical representation of the distribution over songs in each theme by year of release. The box shows the “interquartile range”, from the 1st quartile to the 3rd quartile. This means that half the songs fall inside the box, while a quarter were released in earlier years and a quarter in later years. The solid band shows the median year, which is the year right in the middle of the distribution. The light grey line shows the average year of release. Since most of the distributions are skewed to the left (early years) right (later years) in the interquartile range [see UPDATE below], the mean is a bit higher than the median. The “whiskers” on the plot extend no more than 1.5 times the width of the box. Any outliers beyond the whiskers are shown as points.

Distribution of Year of Release

So what can be made of these distributions? It looks as though love songs are not as popular as they once were and people and places have fared worse still. But while love may be old-fashioned, sex and party songs have become more prevalent and there is still plenty of heartbreak.

And what of the most popular artists? The three most successful artists in Triple J’s Hottest 100 were Nirvana, Jeff Buckley and Radiohead. Nirvana and Radiohead managed one song each in the Guardian’s list: “Lithium” and “Paranoid Android” respectively (both in the life and death theme). Jeff did not make the list, although his father Tim did, with the song “On Top”. The artist with the most entries in the Guardian’s list was Bob Dylan, and the top 12 features a few who did not make it into the Hottest 100 at all, including Randy Newman, Frank Sinatra and The Kinks.

It’s hard to read much more than that into these numbers, but importantly it gave me the opportunity to use a box and whisker plot which this blog has been sorely lacking.

UPDATE: As Mark has commented, this is a bit of a dodgy explanation. There is only so much that can be deduced about a distribution from a box and whisker plot (appealing though they may be). This histogram shows the distribution of the year of release for life and death songs.

Life and Death Theme Histogram

Mark also pointed out that the box and whisker plot does not really show the relative popularity of the different themes over time. I haven’t used pie charts yet, but I am not a fan, so I have come up with a mosaic plot instead.

This confirms the decline in popularity of the love theme, but suggests that, while sex boomed in the 1990s, it has lost ground again in the 21st century. Heartbreak and party songs are the most popular themes of the current decade. The chart also shows that there are more songs in the list from the 60s and 70s than from the 90s, again a departure from the Hottest 100.

I have added this chart to the Guardian Datastore photo pool on flickr.

* To be precise, there are only 988 different songs in the list (and six are duplicated, each appearing in two different categories).