Recently the CM Define It app featured the word graph and we thought it would be interesting to look at how popular this word has been over time using Google Books Ngram Viewer.
Figure 1. Frequency of use of the word graph over time, as a percentage of words in books indexed by Google
When we looked at synonyms of graph, the trend was similar.
Figure 2. Frequency of use of the words plot, diagram, chart and graph over time, as a percentage of words in books indexed by Google Books
The graph above prompts some questions:
- Can we explain the general upward trend?
- Can we explain some of the brief declines during the general upward trend?
- Why is there such a sharp increase in the use of the word graph between 1980 and 1990?
- Why is there a decline in the frequency of use of all four words after 1990?
First of all, when looking at the trends above, it is worth noting that certain words such as plot exist in everyday language and have other meanings (such as a plot of land). This could explain why the term plot shows greater frequency of use very early on, then levels out with the other synonyms in the early- to mid-1900s.
Next, since a graph is a way of representing data, we thought we’d see if these trends could be explained by or related to trends in the word data. Here is the graph with the word data added.
Figure 3. Frequency of use of the word data over time, as a percentage of words in books indexed by Google Books
As you can see, the increase in popularity of the word data is staggering, and dwarfs that of all the previous words. Also, with the recent emphasis on big data and AI it’s tempting to think that the obsession with data is a new phenomenon, but we can actually see that the word data started to become popular over 100 years ago. The popularity of data does show some of the same trends as that of graph, including the ones noted in questions 1, 3, 4 and to some extent question 2, but how can we explain them? To help with this, we’ve indicated on the graph some historical events that we think could be significant.
To address question 1, advances in computing could help to explain a lot of the general upward trend, although we’re not convinced our timeline is adequate. For example, should we also be looking at social and economic factors?
To address question 2, we can see there was a decrease in the use of the word data around the latter half of the Second World War. Could this be because there was less focus on data around that time? What other possible explanations could there be?
To address question 3, the sharp increase up to 1990 could be explained by Moore and Cobb (2000), who suggest that computers started changing how statistics was taught quite early on; for instance, Minitab (a statistical software package for teaching) was developed in the 1960s. At the start of the 1970s, many university departments began using computers for some courses and by the mid-1980s, some introductory textbooks started to include computer exercises. Could the increased use of computers in statistics education explain why the frequency of the words graph and data peaks in the 1980s? Perhaps more textbooks started to feature these words?
How can we address question 4 – the decline in the use of the words plot, diagram, chart, graph and data after about 1990 (with a brief resurgence for data around 2001)? Considering the impact that the Internet has had since the 1990s, this is an unexpected finding. Could the end of the Cold War be a factor?
Do you have an idea as to why the use of the word graph increased so sharply between 1980 and 1990? Or why the use of the words plot, diagram, chart, graph and data has declined since the 1990s (up to 2006, where the Google Books data ends)? If you have suggestions which could explain some of the trends and questions identified, please respond in the comments section below or on our Twitter.
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References:
Moore, D. S., & Cobb, G. W. (2000). Statistics and Mathematics: Tension and Cooperation. The American Mathematical Monthly, 107(7), 615-630.