interactions

Milestone date: 1-Apr-2009
Interactions are the hallmark of information visualization, distinguishing it from information graphics. This is because properly selected interactions can add a tremendous amount of value to a visualization, enabling users to seek out and find answers to the questions they want to ask.

identifying interactions

Basing our exploration on Yi, et. al. 2007, we began the exploration of possible interactions by focusing on 7 possible categories:

  1. Select: mark something as interesting
  2. Explore: show something else
  3. Reconfigure: show a different arrangement
  4. Encode: show a different representation
  5. Abstract/Elaborate: show more or less detail
  6. Filter: show something conditionally
  7. Connect: show related items

The other informative process was to identify the various data entities available to system. Think about each class of data was a useful way to think concretely about the above list of interaction categories. The data types identified are CCEL books, CCEL book authors, biblical books, and biblical/scripture references. Furthermore, scripture references can be aggregated by biblical book (1 biblical book to CCEL book), chapter (1 biblical chapter to CCEL book), or verse (1 biblical verse to CCEL book).

Through looking the categories identified in Yi et. al. 2007 and the above entities, the following possible interactions were identified as potentially valuable to our users.

interaction descriptions

highlight/select CCEL texts and references

This is the primary and most-basic interaction the visualization and can be described as both a select and connect interaction. In order to explore the data points in the visualization, users will use their mouse cursor to highlight individual CCEL books. Doing so will cause information about the book to be displayed as well as the associated scripture references to pop-out from the background. Below are several examples.

highlight example 2
highlight example 1 highlight example 2

highlight/select biblical books and references

Similar to the above interaction, a user should be able to explore the references associated with a particular biblical book dynamically by mousing over the desired book on the x-axis representation of the Bible. Doing so should cause the references associated with that biblical book to appear in the foreground in the same way as the above examples.

search for a ccel book by title/author

Often times a user will be interested in a particular CCEL book or author. In order to facilitate the rapid identification of those items of interest, an auto-completing text input field will be provided. Users can type in either a book title or author and the book will be highlighted in a manner similar to the above examples. This interaction can be described as both a select and a filter operation.

Conditionally hide scripture references

Relative to our initial understanding, there were some surprises in the nature of the data. One surprise that directly affected the representation was the broad-distribution of biblical references that most CCEL books contain, making the initial representation difficult to read. As such, some default filtering of the scripture references is desirable. We accomplished this by filtering out scripture references that did not constitute some minimum percentage of the CCEL book's references (i.e. cutting the tail off of a right-skewed distribution). In the process, it was discovered that various values for this minimum threshold yield different, but equally interesting, results. Therefore, we plan to make this an interaction available to the users as an example of both an explore and reconfigure interaction. Some examples of this interaction follow.

unfiltered
Unfiltered: all references shown
10 percent filtered 20 percent filtered 30 percent filtered
10% Edge Threshold 20% Edge Threshold 30% Edge Threshold
40 percent filtered 50 percent filtered 60 percent filtered
40% Edge Threshold 50% Edge Threshold 60% Edge Threshold


Filter the CCEL books by author lifespan / era

One of the original interactions conceived in the lo-fi stage is to filter CCEL books by their era, as indicated by the lifespan of their author (since accurate data about a book's original publication date is often unavailable). This can be thought of as both a filter interaction and a connect interaction, since a connection is established between CCEL books and their authors. unfiltered fixed

Filter the CCEL books by references to a given biblical book (by chapter or verse)

In contrast, one of the challenges left outstanding during the lo-fi stage was an effective way of showing scripture references at various levels of aggregation (rather than simply as the 1 biblical book to 1 CCEL book level shown above). In light of the focus+context principal, it is important to maintain context of the higher-aggregation level while making this transition to this more detailed level. Furthermore, it was understood that most CCEL users would be most interested in this detail in light of a particular biblical chapter/verse (e.g. "What CCEL books reference Mark chapter 12?" instead of "What chapters does this CCEL book cite?").

unfiltered fixed Above is a somewhat successful attempt to show this detail (one which will be refined further). Here a user has selected a biblical book of interest, and we are displaying scripture references at the chapter-level of aggregation relative to the top x-axis. The CCEL books shown have been filtered to those that contain a reference to the selected biblical book; however, their references to other biblical books remain visible at their previous level of aggregation, preserving context. The CCEL books are placed vertically based on the percentage of their references that come from the selected book, and horizontally based on their reference distribution relative to the selected book.

Navigate to the text of a CCEL book

One elaborate-type interaction that our users are likely to expect is the ability to navigate to the text of the CCEL in question. As such, we can provide links to location of the book on the main CCEL website. It might also be possible to elaborate on biblical references at the verse-level by including the text directly in the visualization.

Reverse y-axis

The decision to use a reversed y-axis in the main visualization is somewhat controversial. As such it provides a good opportunity to include a reconfigure-type interaction. Here we can let users choose the representation that best serves their needs and observe the use of this interaction as a way of establishing an intelligent default.

show proportionally-sized bible axis

Finally, one other way users might be interested in reconfiguring the visualization is by seeing the biblical books sized according to the length of the text contained. This can be used to give a more accurate view of the relative importance (i.e. no. of references / length) of a book as well as make the representation more familiar. However, this was not chosen as the default view because it causes some books to effectively disappear and removes a key affordance of the system (i.e. hovering or clicking on a biblical book).

unfiltered fixed unfiltered proportional
Fixed-width biblical books Proportionally-sized biblical books