Evaluation: Heuristic Evaluation

Adapted Generic principles for heuristic evaluation:

1. Feedback: The child should be aware of what is happening.
2. Everyday child language: Use language that a child would be comfortable with.
3. Consistency: Responses should be the same when similar options are selected by the child and it should share conventions currently in use.
4. Recognition not recall: The child should be able to recognise what they should/can do at a particular step.
5. Simple design: Keep things crisp and simple and aesthetically pleasing.
6. Error recovery: Prevent errors from occurring, but if they do, provide a suitable response and an appropriate solution.
7. Documentation: Any documentation should be simple and concise, as a child will not read it.

General scope of the system:

The system displays a 'scanning' message when the Scan button is pressed. This feedback makes it obvious what is happening. Perhaps a prompt is needed after the word is scanned so the child realises that they can now select the functions that interests them.

The language the system uses is simple and easy to understand for children between 7 and 11, which is especially important for the Dictionary definitions and the Thesaurus entries.

Everytime a word is scanned, the options in the menu remain the same. This ensures that the system is consistant. The system also shares conventions found in devices such as pocket translators/personal organisers and mobile phones, where you scroll through the menus.

As I mentioned under feedback, after a word is scanned the system should prompt the user to select a menu or make it clear that is what is required next. However, due to the system's consistancy and simple design, the next step is easy to recognise.

The word scanner provides only two input controls, namely the scan button and the clickable scroll wheel. This makes interaction simple. The design of the menus is also crisp and simple, avoiding any unecessary clutter.

The system displays an error message when a word failed to scan and also tells the user what to do next, so that they can recover from what they did.

The documentation is short and concise and should only really be required when the user first attempts to scan a word.


Specific interface elements:

The system should prompt the user to select one of the menu options after a scan.

On the menu, the words Dictionary and Thesaurus are ambiguous, they suggest that by clicking them you will be presented with a full system of words/definitions/entries, but this is not the case. They need to be made more specific like Dictionary definition and Thesaurus entries.

Principles from Russell's list that we eliminated:

Undo: The team decided to eliminate this principle. For the word scanner a possible undo function could have be provided for when the user clicks scan after scanning a word, thus losing the word from the device. However, the time it takes to rescan a word is trivial and so the function is not required and for children, adding it may make things more complicated.

Expert use: The word scanner does not have any place for shortcuts or accelerators of any kind, due to the simple scroll interface that the team designed.