This is a key word plot where the text is the file a1f in the British National Corpus (BNC), compared with the whole of the BNC.
You see:
| • | each key word (KW) (these obviously have to do with international relations) |
| • | a measure of its dispersion and its keyness |
| • | how many links each has with other KWs in the same text |
| • | how many times each KW came in the text (hits). |
| • | a map showing where each word came. |
At the left the blue line represents the start of the text, at the right the blue line represents the end. Look at Britain, Germany, Italy and century -- these seem to come in bursts more or less three-quarters of the way through the text. China, Mao, Peking come together a bit later in the text.