Method .1 Subjects

The participants (N = 40) were students at the University of Bielefeld between the ages of 18 and 38. All subjects were native German speakers and had no or only a little experience of playing chess or games with similar rules to chess. They were paid for their participation in this experiment.

8.3.2 Materials

The learning material was concerned with the movement rules of Chinese-chess pieces. Since there were seven different pieces in Chinese chess, all of the instructions were divided into 7 instructional sections. Every section was edited in HTML and presented by means of a program called V-Designer on the computer screen (of the subject PC) with a high color, 16-bit resolution of 1024×768 pixels.

The V-Designer program developed by Thomas Clermont (2001) is a control program for the eye-tracker system. It provides a user-friendly visual programming environment, which enables inexperienced programmers to create their own control program for the implementation of eye-tracking experiments. Moreover, V-Designer is Microsoft-Windows based, so that standard Windows hardware and software interfaces are accessible. Multimedia presentations of experimental stimuli such as video or sound are supported as well. Most important of all, V-Designer provides a solution to the typical problem of timing in Windows environments by implementing an independent timing function, which gives a highly accurate account of run-time behavior (Koesling, Clermont, and Ritter, 2001).

For the first six experimental conditions, each section of the learning material contained a diagram (static picture), a text presented either visually or auditorily, and the links connecting to other sections as well as a link to end the learning program.

The diagram was located in the upper part of the screen whereas the links were embedded at the bottom. The visually-presented text was located in between. Unlike the first experiment, there was no control-bar for subjects to pause or stop playing the auditory text. Yet, subjects could simply press any key on the keyboard to replay the auditory text.

Examples of the learning material can be found in Figure 1 to Figure 5. All the diagrams were 800×600 pixels in size. On the left part of the diagram, there was a drawing (200×200 pixels in size) of a Chinese-chess piece with its name beneath it.

In the simple diagrams, only one possible move (based on the movement rules) for every single Chinese-chess piece was visualized. A blue dot symbolized the starting position of the piece whereas the end-position was marked by a black circle. The blue arrows indicated the direction as well as the length of a possible movement. The links to other instructional sections were put in a table, conveyed by the small drawings (50×50 pixels in size) of the chess pieces with their names above them.

Figure 1: An example of an instructional section of Condition (simp-visu).

Every section contains a simple diagram and a visual text.

In the diagrams with medium complexity, all the possible moving directions from a starting point are visualized. Besides, there were 5 or 6 visual distractors depicted by gray dots in every diagram. The gray dots represent some other pieces on the chess board, and they are additionally used to distract subjects’ attention, and therefore, enhance picture complexity.

Figure 2: An example of an instructional section of Condition (med-visu).

For the complicated diagrams used in complex diagrams, small drawings of the chess pieces instead of the dots were employed. Not only were all possible movements visualized but also more visual distractors were presented in the diagrams.

Figure 3: An example of an instructional section of Condition (comp-visu).

Figure 4: An example of an instructional section of Condition (comp-audi).

In this condition, subjects were given auditory text.

For the last two experimental conditions, I employed animation for displaying the movement rules. Again, animation was presented with either visual or auditory text. The same number of visual distractors shown in Condition (comp-visu) and Condition (comp-audi) were fitted in the background of the display of animation as well. Figure 5 shows an example of an instructional section of Condition (ani-visu).

Figure 5: An example of an instructional section of Condition (ani-visu).

The chess piece for which the rules were described by the instruction was marked with a blue circle every time in its starting position shortly before it moved to a possible position on the chess board. The animation showed how the piece moved to all the possible positions that it could potentially reach in one move from its current position. In some instructional sections, the positions to which a chess piece was not allowed to move were signaled by inserting red crosses in the referential positions.

8.3.3 Apparatus

The same SMI EyeLink eye-tracking system as in Experiment 1 was used to measure subjects’ eye movements. There was, however, a change in the hardware of the subjects’ PC which contained an AMD Athlon 600 MHz processor and a new graphics card (ELSA ERAZOR III). With the aid of the new graphics card, the stimuli viewed by the subjects during the experiment were delivered directly in the form of video signals to the VISCA recorder, so that the sequences of stimuli viewed by each subject could be videotaped. The synchronization of eye movements and the video was again carried out by the Viper program.

8.3.4 Procedures

On arrival, subjects were asked about their experiences of playing chess or games similar to chess, so that the number of subjects with different amounts of experience (chess experts were excluded) could be balanced between conditions. Subsequently, basic information about Chinese chess as well as their respective tasks were introduced to subjects. After calibrating the eye-tracker, another instruction concerning how to use the learning environment was shown on the screen of the subjects’ PC. Subjects were asked to learn the movement rules of Chinese-chess pieces on the computer with concentration. There was no time limit for learning, but subjects were asked to learn the information as quickly as they could. When the subjects finished learning, they were given a test to assess their learning results and another test to roughly estimate their prior knowledge of chess. In addition, they had to fill out a questionnaire which comprised more or less the same questions as did the one used in the first experiment.

There were eight questions in the test for assessing subjects’ learning results.

Each question tested the movement rules of a Chinese-chess piece. For example, the question for testing the rules regarding the elephant is shown in Figure 6. Subjects were asked to mark the piece or pieces which was/were threatened by the blue

elephant. There were two questions about the piece “soldier” because the rules were different depending on which zone the soldier was in.

The test for estimating prior knowledge of chess consisted of six questions.

Subjects had to write down the definition of the following six specialist terms regarding chess: blitz tournament, en passant, ELO, castling, gambit, and fictitious attack. The score a subject achieved in this test was supposed to be positively correlated to his or her prior knowledge about chess.