1.3.3. Assessing relevance

Petrol finder

(Reichenbacher 2005) identifies different types of relevance, here we focus on his four main types:

• Activity relevance – how is the information relevant to what the user wants to do?
• Spatial relevance – does the information vary spatially, so that it is relevant to the user’s changing location?
• Temporal relevance – does the information vary over time, so that it is relevant to the time when it is accessed?
• Thematic relevance – what particular aspects or properties of the information have special relevance to the user (e.g. brand of a restaurant)?

We will use these ideas about relevance to identify useful information contained in a database describing petrol stations. This is drawn from a real information service provider (Catalist). The dataset includes all manner of information about the situation, functions and services of the stations. These will be relevant in different ways for different types of service. You will need to mark each data item as either irrelevant or; activity, temporally, spatially or thematically relevant, in relation to one of three car journey tasks. The activities that you can choose from are:

• Finding fuel
• Stopping for a rest break
• Last minute shopping.

The aim of this exercise is to analyse a real data resource and identify which data items are most relevant to the activity chosen, in relation to four main types listed above. Selecting an item from the list in the left hand box allows you to mark whether you think the item is relevent spatially, temporally, thematically or with respect to the theme. Mainly an item will only satisfy one of these criteria, but you may have reason for selecting more than one relevance type. Your selections for each item will be shown together in the lower box. Discuss you choices with your fellow students and have your tutor review your analysis (if required, you can select the text of the lower box and save your final analysis).

Questions to consider

How might the different types of situation information be used in different forms of information portrayal of your services (e.g a map or a set of text-based route instructions)? (Click here for more information)

In deciding how to define a symbol style for a petrol station on a map you will be limited in how much information you can present in the graphic. Hence you should only show what you consider to be the most important data items. What type of relevance and which data items would you use as the main criteria for defining a symbol graphic? (Click here for more information)

How would you present the remaining data items to the user? (Click here for more information)