N341 Card Sorting
According to several surveys, most people respond to the question of "What do you hate most about the Web" with "I can't find what I'm looking for", meaning they are often lost. Good content organization creates the foundation for effective site navigation.
Much of the following discussion is based on the project, the stock trading Web site.
The previous discussion illustrated site organization but did not answer the question of "how to organize content so people can find what they want". The following presents methods for gathering content and determining an appropriate organization.
Objects - Form the site content.
Actions - Tasks the user performs.
Analyze the proposed Web site for objects (nouns) and actions (verbs).
Refer to existing documents such as a catalog for an e-commerce store site, written procedures for existing tasks, and, of course, the user and task analysis.
Avoid repetitive terms such as: enter name, enter password, enter stock, enter amount, etc. that create an artificial group of terms.
For the air flights site, some important objects and actions are:
Objects Actions passenger
What are at least 6 objects for stock trading?
What are at least 6 actions for stock trading?
Organizing ambiguous content is best done by users essentially voting on how to group content items.
Groupings may indicate that items are synonyms or that grouped items can be placed on the same page as content or tasks.
One organizational method is card sorting for which the manual version is performed by:
- content items are written on 3x5 cards and uniquely numbered on the back.
- scatter the cards
- users sort cards into piles of related items
- users write name for each pile on Post-It note
- turn cards number side up and record grouping for each user
- look for commonalities in grouping, such as the number of times card 3 and 4 were in the same pile.
There is no correct number of piles except more than one.
- Each time two cards are in the same pile assign 1 point.
- Add up all the times two cards are in a pile together and divide by the number of users. If all users place cards 3 and 4 in a pile, the similarity rating is 1, if no one did, the rating is 0.
Example - The following is a partial analysis of card 1 grouped with 2, 3, 4 and 5 as sorted by 4 users, A-D.
Card sorting raw data results User A User B User C User D Sum Similarity Rating 1,5
Score Cards 1 and 2
Cards 1 and 3
Cards 1 and 4
Cards 1 and 5
0/4 = 0
0/4 = 0
1/4 = .25
3/4 = .75
Apply card sorting to the objects and actions of Exercise 1.
Determine the similarity rating of cards 2 and 1, 3, 4 and 5 in the above example.
Card sorting tools are available, USort for entering and sorting the cards and EZCalc for analysis.
EzCalc displays similarity results as tree diagrams using three analysis algorithms ("Complete", "Single" and "Average"). In brief, Single linkage algorithm emphasizes more on similarities, while Complete linkage algorithm emphasizes more on differences. Average algorithm gives a balance of these two algorithms. So, each algorithm provides information structure at a different angle. For more information about the statistics principles of the three algorithms, visit http://www.statsoftinc.com/textbook/stcluan.html#a.
Distance from cards is used instead of a similarity rating. A distance of 0 means that everyone placed two cards together. In the Distance Matrix below, everyone combined 2 and 3 in the same pile. A distance of 1 means no one combined the two cards.
The average results displayed as a tree indicates cards 2,3 were grouped together by 100% of users (i.e. distance 0), cards 1,5 were grouped together by about 75% (i.e. distance .25). More complex groupings such as 2,3 with 1,4,5 indicate a high distance or low similarity rating.
Distance Matrix: (1) (2) (3) (4) (5) 1 (1) 1.0000 1.0000 1.0000 0.7500 0.2500 2 (2) 1.0000 1.0000 0.0000 0.7500 0.7500 3 (3) 1.0000 0.0000 1.0000 0.7500 0.7500 4 (4) 0.7500 0.7500 0.7500 1.0000 0.5000 5 (5) 0.2500 0.7500 0.7500 0.5000 1.0000
User A User B User C User D 1,5
Enter your stock trader card numbers into the USort program.
- Click: "I am a study participant".
- Enter your name.
- Close the instruction window.
- Enter or select: Stock.cld
- There are 10 cards at the left. Sort the cards by dragging from left to right side.
- When done, Þ to Step 2, double click on the single lines between piles. The lines should now appear as =====.
- Save your results.
- Email the yourname.esd file to email@example.com.
The instructor will analyze the results of the card sorting. To do so yourself:
- Download and install EZCalc
- Execute EZCalc.
- Click: File | New
- Enter: Stock.rec
- Click: Add from a Participant Data File.
- Add all the files with .esd extension.
- To view graphs click one of: Complete, Single, Average buttons.
- To view the distance matrix click: Matrix
What can you say about organizing stock trading content?