Periphsummary1
From EQUIS Lab Wiki
an intrusive evaluation of 3 different peripheral display systems on the same financial data set.
found that there was a significant different on a primary task perfomance and a peripheral comprehension task between large and small displays as well, distraction may be composed by display-distraction and self-interruption and animation may only influence the display distraction
Intrusive Evaluation - where the user is consciously aware of the evaluation experiment. This kind of evaluation often focuses on usability tests in a laboratory environment for a short period of time. Most often, such experiments are conducted using mainstream evaluation methods in information visualization (i.e. questionnaires, interviews and think aloud).
3 displays are compared: digital data, meytree and stock chart
Digital data is a normal numerical visualization of financial data. It uses textual display to represent trade price and volume It neither keeps previous trading history nor uses animation during transitions.
MoneyTree is a graphical display to represent financial data. It uses three different types of trees to represent three individual stock quotes and also uses tree length and leaves to represent the trade volume and price respectively. No visualization history is depicted but image morphing is used to achieve smooth graphical transition from one stage to another.
Stock Chart is a traditional financial visualization, which uses three different colours to represent three stock quotes; a linear curve represents trade price and a bar chart represents trade volume. This shows trading history but there is no animation used in transition from one stage to another.
aim of the experiment was to discover the difference in the context of distraction, comprehension and efficiency between large and small displays
16 subjects 8/8 male/female participated all with normal eyesight..
2 standard 19 inch desk moniters were used in small displays and 2 large rear projection screens used in large displays
In each peripheral system, two tasks were involved: primary task and secondary task. The primary task was to allow subjects to type words on the primary screen for two minutes while the peripheral system was displayed on the peripheral screen. The typed words were from Shakespeare’s Hamlet and were printed on a one side A4 size sheet paper with a 16 point font. The secondary task was to occasionally shift focus to the peripheral screen to get information about the three stock quotes.
Three detailed hypotheses- H1: Large display performs better than small display in terms of comprehension; H2: Large display achieves higher efficiency than small display; H3: The more times subjects shift their focus to the peripheral screen, the more information they will get.
Within each experiment, there were four sub-tests (primary task plus Digital Data, primary task plus MoneyTree, primary task plus Stock Char and primary task without peripheral display).
results
A paired student’s t-Tests was used to analyze the results and a Z Score was used to calculate the efficiency level Three independent parameters were analyzed: Mean Comprehension Error Rate (MCER), MeanWord Typed (MWT) and Mean Focus Shift (MFS). used MCER to measure the comprehension in each test; use of MFS to measure the distraction and use of a combination of MCER, MWT and MFS to measure the efficiency.
results reveal that large displays have a higher MCER than small displays and this difference is significant
large displays achieved lower MWT than small displays in all three tests and the difference was significant
large displays have lower efficiency then small displays but the result is not significant (needs further study).
