## 3 Preferences Evaluation of Information Delivery Elements of TV Broadcasts for DHH Individuals
### Experiment Environment  
This experiment was conducted for 30 DHH participants in two laboratories as shown in Figure 9 at the shelter for the DHH people run by the Gwangju city branch of the Korean Association of the Deaf. The subjects of the experiment were people with hearing impairment over the age of 20; the age range of subjects was from 30 to 60 and there were 24 females and 6 males. Regarding educational background, there were those without education (2), middle school graduates or lower (8), high school graduates (11), and college graduates (2). The experiment consisted of a total of three people: a subject, a sign language interpreter to help guide the experiment progress, and an investigator. Tobii Nano, an eye tracker, was attached to a 27-inch monitor to collect gaze information from the subject during the experiment.  
\begin{table}
\begin{tabular}{c c c} \hline \hline  & **Test Step1** & **Test Step2** \\  & **Basic Type** & **Subtitle Added Type** \\ \hline  & \(\bullet\) Sign language interpreter’s placement—Right side \\ \hline  & \(\bullet\) Separation of a sign language interpreter and the  
Prior to the experiment, a survey was conducted on the level of the use of sign language and Hangeul (Korean language) among the subjects. The results showed that 93.5% of the 30 subjects had used sign language for more than 10 years, but only 74.2% of them had received regular sign language education before. A total of 45.2% of the subjects answered that there was an expression they did not know when using sign language. In addition, when asked about the use of character language, 71% of them answered that they had received Hangeul education and used Hangeul for more than 10 years. However, 83.9% answered that they felt difficulties due to the different systems of Hangeul and Korean sign language.  
In this experiment, the subject was asked to select the most preferred subordinate option after watching the step 1 video clips for each broadcast type as described above. In step 2, they watched a video with subtitles added to the layout type selected in step 1. After completing step 2, they were asked to evaluate their preferences for all layout types that they watched in the 2 steps of the experiments. In addition, individual interviews were conducted to investigate the reasons for their preferred layout type. Each subject was asked to evaluate two types at random. An average of 20 subjects responded per type. For the eye tracking of the subjects, the eye movement path of the subjects and the frequency of gaze for each component of the screen were identified by using the screen-attached eye tracker \"Tobii nano\", which is a convenient device for tracking the user's gaze on the monitor screen [24].  
Initially, the experiment was designed with each subject answering a total of three phases of questions: one for each type (news, panel discussion, weather forecast). However, this took more than one and a half hours since the majority of the subjects were found to experience difficulties understanding and answering the questions after watching the video clips. A sign language interpreter helped them understand the experiments, but the experiment did not progress as smoothly as expected. Considering the fatigue of the subjects, the experiment design was changed so that one subject watched two clips for each type, and an average of 20 subjects participated in watching and answering sessions for each video type. Compared to the subjects with normal hearing, the experiments on the subjects with hearing loss took two to three times longer.