Predictive software
Description
As characters are entered into the computer, either via the keyboard or by alternative input method, the software endeavours to predict the word being written. The user is offered a list of possible words. If the required word is offered, it can be selected and is placed in the document. Common features include automatic capitalisation of proper nouns and words beginning sentences and automatic spacing between words. Many systems ‘learn’ the more common words used by a user and, thereby, improve likelihood of offering the required word earlier in the process. As well as screen-based feedback, synthetic speech output is also often provided. Note that on-screen keyboard software usually includes word prediction. Another feature often included in predictive software is abbreviation expansion. This allows the user to produce a word, phrase or, in some cases, pages of text with as few as two keystrokes. It should be remembered that some popular word processors have some of these features. In particular, programs such as Microsoft Word offer abbreviation expansion and other useful facilities.
Advantages
For some people who enter text very slowly, predictive software (also called word prediction) may increase writing speed. It also reduces the amount of physical effort required which, for some people, can be considerable. While important for preparation of documents, it may be even more vital for people who use augmentative communication devices.
Disadvantages
For some people, it reduces speed, due to the need to scan the word prediction window. The facility may be less effective for some people with limited literacy levels and/or poor vision. It may be tedious for people who can type at more than 10 to 12 wpm. A potential disadvantage is that display of choices can require considerable reading. However, this can be resolved with careful design. If speech output is required due to vision impairment, selecting the appropriate word can become somewhat tedious.
