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OVA – User Guide last updated September 3, 2009 by

OVA – User Guide


Getting Started

You can start using OVA by visiting its website at [coming soon!]. You can then either:

  1. Enter the URL of the page you wish to analyse into the box
  2. Drag the “Bookmarklet” to your browser bookmarks bar and analyse a page by clicking the resulting button (see Bookmarklet at Wikipedia).

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Extracting Text

The core feature of OVA, as with Araucaria, is the ability to extract text into a series of premises, which are then used to construct an argument diagram.

Doing this in OVA is very simple:

  1. When the page has loaded, identify a piece of text you wish to extract
  2. Highlight this text, then click on the white “canvas” in the OVA interface
  3. Repeat for all premises you wish to add

The software has been designed to safeguard against duplicate premises. That is, you cannot extract exactly the same piece of text twice by accident.

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Joining Premises

In order to indicate support or attack, premises must be connected. This is done by the following procedure:

  1. Identify the premise you wish to be the supporter/attacker and hover your mouse cursour over it.
  2. Hold down the SHIFT key on your keyboard
  3. Click your mouse, but don’t release the button, or the SHIFT key
  4. Drag the cursor to the premise you wish to support/attack. You should see a black line being drawn to follow the drag of the cursor
  5. Release both the mouse and the SHIFT key when over the premise and a connection should be established, with a “Scheme Node” in the middle

To create a linked argument (that is, an argument in which two or more premises work together to support or attack another):

  1. Establish the first link by the procedure above
  2. For the second premise, carry out steps 1 – 3 above
  3. Instead of dragging the cursor to the premise you wish to support/attack, drag it to the already created Scheme Node. The link will then be established to this, indicating a linked argument

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Setting Schemes

OVA has a number of built-in schemes, grouped by schemeset. To apply one of these to an argument:

  1. Right-click on a Scheme Node and click “Set Scheme”
  2. A popup box will appear with two drop-down menus; the top menu will be populated with schemesets. Select a schemeset from this menu
  3. The bottom box will now be populated with the schemes contained in that set. Select a scheme from this menu
  4. Click “OK” and the scheme will be applied to the argument

Custom Schemes

OVA also supports the creation of custom schemes. This can be done in one of two was:

Via Scheme Nodes

  1. Right-click a Scheme Node and click “Set Scheme”
  2. On the popup box, click “Add Custom Scheme”
  3. You will be presented with an interface to enter the scheme information into: provide the scheme with a name, conclusion, at least one each of premises and presumptions (“critical questions”), and indicate the type (Rule, Conflict or Preference)

Via the “Custom Scheme Manager”

  1. From the “Tools” menu click “Manage Custom Schemes”
  2. Click “Add Scheme” and carry out step 3 above

You can also use the “Custom Scheme Manager” to edit previously created schemes. You can do this by simply clicking on the name of a scheme listed in the manager and changing the details (note: it is not possible to change any of the built-in schemes).

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Adding Missing Premises

Sometimes an analysis requires the addition of a missing premise or enthymeme. These can be easily added:

  1. From the “Tools” menu, select “Add Missing Premise”
  2. In the box that opens, enter the text of your missing premise
  3. Click anywhere on the analysis canvas; the box will close and your premise will be added

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Deleting Premises/Scheme Nodes

You can delete any premise or scheme node in your analysis by right-clicking on it, and clicking “Delete Node”. Note that deleting a Scheme Node will delete any links that go through it.

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Toggling Scheme Nodes

If you prefer to view the analysis without scheme nodes, you can toggle them on the diagram. To do this, from the “Options” menu click “Toggle Scheme Nodes”.

Note that even with Scheme Nodes turned “off”, they will re-appear when linking premises to allow linked arguments to be created.

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You can zoom in and out by using the slider at the top of the screen.

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Saving to database

OVA provides an interface to allow you to save to an ArgDB installation. The version of OVA available on this site connects to an ArgDB server here at the university, which you can save to.

  1. From the “Save” menu, click “Save to database”
  2. In the “Select a server” drop-down menu, ensure that “University of Dundee” is selected
  3. Enter a title for your analysis
  4. Enter your username and password (optional; see below)
  5. Click “OK”; after a few seconds, a popup will appear indicating whether or not the save operation has been successful; if it has succeed, you will be given an ID number for your analysis which can be used to retrieve it again (see below)


You are not required to register in order to save analyses to our ArgDB server, however we recommend you do register so as to provide an easy method of retrieving all your analyses again. To register, simply click “Register on this Server” and provide a username and password.

Retrieving Analyses

In order to retrieve an analysis saved on our ArgDB server, visit<id>, where <id> is the ID number you were provided with in step 5 above. Alternatively, click here and enter the ID in the box.

Saving to local AIF file

If you wish to obtain an AIF file from your analysis without saving to ArgDB, you can do this by clicking “Save to local file” in the “Save” menu.

Saving to image

You can also save a JPEG image of your diagram, by clicking “Save to image” in the “Save” menu.

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