## 1 Introduction  
The concept of user experience (UX) was introduced to overcome the shortcomings of traditional usability evaluation methods (UEMs). [1] defines usability as \"the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency, and satisfaction in a specified context of use.\" Although some researchers have tried to embrace constructs such as impression and image to explain the concept of usability [2, 3], in general, usability is considered as a performance-related measure which hardly represents the various contexts of use that exist for products or services.  
The definitions of UX are diverse and abstract. [4] defines UX as \"a person's perceptions and responses that result from the use or anticipated use of a product, system or service.\" The definition could be more abstract as \"an overarching experience that consists of all aspects of users' interaction with a product or service\" [5, 6, 7, 8, 9].  
However, because of its ambiguous and abstract aspects, quantifying the level of UX is difficult. There is no general consensus among researchers on the specific elements which compose UX. For instance, [8] decomposed UX into elements consisting of usability, affect, and user value, while [10] suggested that three perspectives compose UX: beyond the instrumental, emotion and affect, and the experiential. Furthermore, researchers have reported that UX depends on temporality and varies over time [11, 12].  
Consequently, in order to evaluate a level of UX in the use of product or service, researchers must first identify the UX elements and then decide how to quantify the elements. Even if the specific elements into which UX should be decomposed are unclear, value as a general term is undoubtedly related to UX. Value, if it can be comprehensively extracted from users and can be measured, is an important measure that represents users' perceptions and responses toward the product or service.  
In the fields of marketing, psychology, and industrial design, many studies have focused on defining and quantifying the value. [13] suggested eighteen terminal values (e.g., true friendship, mature love, and self-respect) and eighteen instrumental values (e.g., cheerfulness, ambition, and forgiveness) that refer to desirable end-states of existence and modes of behavior, responsively. Although these values were widely adopted by various value researchers, many studies focused on the individual aspect rather than the product-related aspect. [14] associated these values with product choice. Note that [15; 16] defined user value as \"desirable states of existence or modes of behavior which are satisfied when using a certain product or service.\" Recently, values have come to be recognized as important measures to explain users' product or service experiences.  
The objective of this study is to suggest a practical approach to developing the value structure for a specific product or service usage. To formulate the value structure, this study proposes to apply co-occurrence-based network analysis on users' descriptions about their experiences of interaction with specific product and service in a given context. Since the proposed method adopts the network analysis, a series of mathematical analysis could be used in the analysis of keywords, without predetermining a set of keywords of interest. To demonstrate the proposed process of developing the value structure, gesture interaction adopted in smart TV was used as a case study. The various advantages and limitations of a value structure that contains mathematical information are also discussed.