TermsRadio provides a scrolling line graph that can depict the change of the frequency of word across a corpus spread over time.

Getting Started

When you first arrive to the TermsRadio tool you will see one of two possible screens:

TermsRadio-without-corpus TermsRadio-with-corpus

TermRadio without a pre-loaded corpus. See loading texts into Voyeur for help on how to proceed.

TermsRadio with a pre-loaded corpus. You were probably given a URL that included the corpus, or you’re viewing a page that has an embedded Voyeur tool in it. If you prefer, you can also start without a corpus.

Interface Elements

TermsRadio includes the standard set of interface elements (see image below). For more help with these see the Voyeur Tools Standard Interface Elements page.

Standard UI Elements

Reading the tool

The main body of the tool displays a line graph that slides to depict changes in the frequency of a word within a corpus spread over a period of time. Each of the lines in the graph represent a word. The words that have been selected are indicated in the legend. Each word in the legend is coloured to match the colour of the line that it is associated with. The legend starts in the top left-hand corner but can be dragged around to the convenience of the user.

Above the graph body is the Navigation bar, this area demonstrates the line graph for the selected words over the entire corpus. If no words are selected the area will be blank. The navigation bar also indicates which section of the corpus is presently being viewed in the body of the graph. This section is delimited by two black bars, the area that is viewed has a white background where the area that is not being viewed has a grey background. As the graph scrolls through the segments of the corpus the viewed section in the navigation bar will move too.

To the right of the graph body is the Y-axis bar. This bar demonstrates the portion of the original frequency range present in the corpus that is displayed in the graph. The graph will always excludes a certain number of low frequency words. The manner that this is done is by selecting the top ‘n’ most frequently occurring words (the value of ‘n’ is controlled with “Word Display” menu on the bottom toolbar) and excluding the rest. So the y-axis bar depicts how the lowest frequency of the included words measure up against the full range of word frequencies in the corpus. This difference is visualized by length difference between the bar without a fill overlayed by the war with fill. In many cases the difference will only be a sliver between the two bars at the bottom.

The scrolling of the graph is controlled through a number of features on the lower toolbar. They are fairly self-evident, “Forward” begins scrolling the graph forward, “Back” begins scrolling the graph backwards, and “Pause” stops the scrolling. As well “Reset” resets the graph to the beginning and “Scroll speed” adjusts the speed at which the graph scrolls. One other method for navigating is through the “Navigation bar”, clicking and dragging on the greyed out section of the bar to the desired section of the corpus will automatically bring the graph to display this section. If the number of visible segments is set to the maximum then the scrolling features will be disabled.

Configuring the display

TermsRadio has several options for configuring how the graph is displayed. These options are found in the lower toolbar and include the drop-down menus “Word Display”, “Segments”, and “Visible Segments”.

  • “Word Display” controls the number of words that are displayed in the graph. For example 20 will display the top 20 most frequent words, 40 will display the top 40 most frequent words, and so on.
  • “Segments” controls the number of segments that the corpus is split into. This feature is only available if the corpus is comprised of a single document, otherwise the corpus will contains as many segments as there are documents in the corpus.
  • “Visible Segments” controls the number of segments that are visible in the body of graph at any one time. If the corpus is divided into less than five segments then “Visible Segments” will be disabled and all segments will be visible.


Adding and removing words

While all the words are present in the graph body as data points, a line indicating their frequency trend is not present unless the user selects the word. Selecting the word is possible two different ways. Firstly a word can be selected by clicking on the word in the graph body. Secondly the word can be selecting through the search box in the lower tool bar. When the user begins typing the toolbar will provide a number of auto-complete suggestions. To select the word either finish typing and press “Enter” on the keyboard or click the word from the auto-complete list. To deselect a word click the word once again in the graph body, click the word in the legend or enter the word in the search box.

While the mouse pointer is hovering over a word it will be selected similarly to clicking on the word. A line in red will appear in the chart body and in the Navigation bar indicating the word’s frequency trend. However as soon as the mouse pointer is moved off of the word it is deselected. Hovering over a word will not add it to the legend.

Important options

Within the options panel TermsRadio allows for the user to toggle between a logarithmic scale and a linear scale for the y-axis. The default setting for TermsRadio is for the y-axis to be scaled logarithmically.


Linking from the tool

Double clicking on one of the words in the legend will open a new instance of Voyant Tools with a focus on that word.


Like all Voyeur tools, TermsRadio can be reused in a variety of ways:

  • create a link that is specific to the corpus and options that are currently being used
  • embed the current corpus and options as a tool in an external page

For more information see exporting and reusing Voyeur Tools.