# Speech Characteristics as Indicators of Personality Traits
## 1 Introduction  
Language can be a useful window through which we can understand the social and psychological attributes of its users, including personality traits. The utility of language in identifying personality has long been recognized and investigated [1, 2, 3, 4, 5, 6, 7], with many recent studies observing correlations between specific language features and certain personality attributes. For example, [PERSON] et al. (2009) [8] and [PERSON] et al. (2009) [9] showed that linguistic and interactional features such as speech rate, pitch range, and laughter are closely related to friendliness or fliratiousness, to an extent that these features can be used in detecting the speaker's intent to be friendly or to be fliratious at above 70% accuracy. [PERSON] et al. (2012) [10] identified a number of acoustic features such as loudness or voice quality that can be used to recognize speakers that exhibit personality characteristics of leadership (e.g., high-achieving, charismatic, team-playing, etc.). [PERSON] et al. (2019) [11] observed that certain linguistic items, such as sports-related words,wear words, and second-person pronouns, may mirror narcissistic personality. Studies have also examined how language reflects personality dimensions identified by the Myers-Briggs Type Indicator (MBTI) model. The MBTI model measures four personality dimensions of introversion-extroversion, sensing-intuitive, thinking-feeling, and judging-perceiving, and attempts to describe an individual's personality as one of 16 types. The MBTI model utilizes a series of questions that are designed to gauge a person's inclinations for outwardness, sociability, reliance on senses, orderliness, and so forth. Respondents to the MBTI questionnaire answer a series of questions on a Likert scale (e.g., very unlikely to very likely). Based on the compiled answers, the model proposesthe likelihood of the person's introvertedness (compared to extrovertedness), the degree of sensing (compared to intuiting), that of thinking (compared to feeling), and that of judging (compared to perceiving). The introverted/extroverted dimension reflects a person's orientation toward the outer world. The sensing/intuiting dimension differentiates individuals based on how memory and information is processed and stored; a prototypically sensing individual processes information by relying on physical, sensory vehicles, but a prototypically intuitive individual places a subjectively determined interpretative lens when processing information. The thinking/feeling dimension reflects one's style of interaction or decision-making; \"thinking\" individuals are more logical, task-oriented, and less compromising in prioritizing values, whereas \"feeling\" individuals are more flexible and tactful in making decisions, actively taking into account different contexts and situations. The judging/perceiving dimension groups individuals based on whether they appear more structured and orderly in carrying out daily tasks; the judging types are thought to be more orderly, while the perceiving types are thought to be more open in selecting and prioritizing what is to be done next. Of these different personality dimensions, the most commonly investigated dimension is extroversion, though there are studies that explore the relationship between language and other personality dimensions in addition to extroversion, such as conscientiousness, agreeableness, neuroticism, or openness [7; 12; 13; 14]. Studies have identified a number of linguistic characteristics that are associated with extroversion; it has been found that extroverted (or \"outgoing\") Dutch speakers tend to use linguistic markers of abstraction more frequently than introverted Dutch speakers [15], and also that extroverts tend to be more verbose than introverts [16; 17; 18; 19; 20]. Relatedly, extroverts were observed to exhibit higher verbal fluency not only in their own speech [21], but also during interaction as manifested with their shorter response time [22; 23].