Single Item Search on PDAs: Effects of Font Size & Menu StyleBy Ketan Babaria, Sasha Giacoppo, Ugur Kuter

Desktop Vs PDA

Desktop13” or largerHigh resolution: 1280x1024 pix

PDA3” – 4” diagonallyLow resolution: 240x320 pix

Previous Font Size Results

Hypotheses

1) Detailed View searches take longer, with more errors, than List View searches

2) There is a critical point where font size decreases item selection time and increases error

Independent Variables

Font size Small font (10 pt) Medium font (12 pt) Large font (14)

Menu type Expanding Detailed (Scrolling)

Item distance 1/3 down the list 2/3 down the list

Task Design

3x2 interfaces (6 total) Detailed small, detailed large etc Expanding small, expanding large etc

For each interface users were given the name of the food item and then they had to search for that item.

Interfaces – Expanding Menus

Expanding Menus – Cont’d

Interfaces – Detailed Menus

Detailed Menus – Cont’d

Dependent variables

Item selection timeNumber of errorsSubjective satisfaction

Results

Results

Significant reduction in performance fo expanding menusSmall font size had maximum errorsNo significant difference in errors using medium and large font sizeInteraction between distance, font size, and menu typeHigh correlation between task time and “screen clicks”

Conclusion

Don’t make font sizes too small More selection errors

Scrolling menus better than expanding Less navigation Requires less cognitive effort of the

user