## 1 Introduction
### Related Work  
In some situations, unintentionally speakers tend to communicate emotions through many nonverbal cues which derive mainly from facial and vocal behaviors [12]. In a conversation, vocal cues of a speaker dramatically influence the perception and appraisal of a social interaction especially when it involves out-group listeners. Joy is expressed with a comparatively rapid speaking rate, high average pitch, and large pitch range. Sadness is conveyed with a slow speaking rate, low average pitch, narrow pitch range, and low intensity. Anger is expressed with a fast speaking rate, high average pitch, wide pitch range, high intensity, and rising pitch contours. Fear is conveyed with a fast speaking rate, high average pitch, large pitch variability, and varied loudness [13]. These emotional cues are well documented for English speakers; however, there might be certain differences in vocal qualities that are associated with emotion in other languages (e.g., Asian languages). Prosody features (intensity, vocal pitch, rhythm, rate of utterance) contribute in forming the different expressions of emotions which are used to decode the meaning of a person's speech [14; 15; 16]. [PERSON] and [PERSON] (2002) found that members who shared similar cultural elements (e.g., degree of individualism or collectivism, power structure, and gender roles) are more successful at interpreting each other's emotional expressions than non-members of that culture. For example, cultural closeness predicts that Japanese people should be better at recognizing the emotional expressions of Chinese people than the emotional expressions of Americans because Japanese and Chinese cultures are more similar in terms of relevant dimensions compared to Japanese and American cultures [17]. This discrepancy indicates that socio-cultural influences on emotion recognition are noticeable in the vocal channel due to the unique interplay of emotion and language in speech. In this context, \"natural\" cues to emotion in the voice are tightly intertwined with the acoustic-phone properties of individual speech sounds [9] In a similar vein, linguistically assigned differences in the segmental inventory and intonational features, which contain the accent and rhythmic structure of a foreign language, could also impact emotion recognition by interacting negatively with the basic aspects of auditory speech processing or with the processes for extracting salient emotional features from prosody [9]. In a perception study by [PERSON] et al. (2003), native speakers from nine different countries across three regions (e.g., Europeans and Malays-Indonesians) were presented with 30 emotionally-modulated but semantically-anomalous utterances produced by four German actors. The researchers found that all listener groups recognized fear, joy, sadness, anger, and neutral utterances strictly from prosody at above-chance accuracy. The results emphasized that German (native) listeners performed significantly better on this task compared to the other language groups. It was apparent that language similarity appeared to influence vocal emotion recognition because listeners whose native language was more linguistically similar to German (e.g., Dutch) tended to be more accurate than those from a highly dissimilar language (e.g., Malay). These data imply that language and cultural features play an important role in how vocal emotions are recognized and decoded [10]. Another experiment by [PERSON] and [PERSON] (1972) investigated emotion perception using English sentences that were of different length and accent [18]. The study revealed that in-group listeners (Americans) outperformed out-group listeners (Japanese) beyond chance level when listening to shorter utterances (e.g., \"hello, how are you?\"). However, this in-group advantage was not apparent when recognizing emotions from longer sentences, suggesting that the duration of an utterance affects the perception rate.