Indonesian Generation Z’s Intention to Visit South Korea: The Mediating Role of Tourist Attitude on Travel Motivation and Celebrity Endorser Credibility

Objective: This study examined the effect of travel motivation and celebrity endorser credibility in influencing the intention of the Indonesian Generation Z to visit South Korea, with involved a mediating role of tourist attitude, which refers to the Korean Wave Phenomenon. Design/Methods/Approach: This study was done by quantitative approach with Partial Least Square Structural Equation Modeling (PLS-SEM) analysis procedure using SmartPLS 4. The data collection technique was purposive sampling, aimed at the Indonesian Generation Z as the target respondent. There were 385 data collected using the online questionnaires. Findings: The results show that travel motivation and celebrity endorser credibility positively and significantly affect the visit intention to South Korea. Tourist attitude also mediates the relationship between travel motivation and celebrity endorser credibility in affecting the visit intention to South Korea. Originality: The existing literature discovered the direct effect of travel motivation and celebrity endorser credibility on visit intention in the tourism industry. This study contributes to the existing literature by involving tourist attitude as a mediation variable in the relationship between tourist motivation and celebrity endorser credibility in affecting visit intention to South Korea. Practical/Policy implication: This study contributes to proposing recommendations for a more effective marketing and promotion strategy for tourism products in South Korea by looking at trends in tourist preferences and involving the role of celebrities as an endorser. Research also contributes to developing literature on marketing and promoting tourism products and tourist behavior literature.


Introduction
Tourism is one of the important industrial sectors for a country, which can help the acquisition or increase the country's foreign exchange. Tourism is a traveling activity involving various aspects, such as individuals, activities, and facilities (Cook et al., 2017) and also involves various other business sectors, such as destinations, culinary, handicrafts, shows, and others, that could attract the attention of potential visitors or tourists. An individual is encouraged to carry out a traveling activity related to the individual's behavior. Yousaf et al. (2018) explain that tourist behavior based on the aspects of tourist psychology could shape the desire to visit a particular destination. In addition, the individual's encouragement in traveling activities could motivate people to travel, which is based on the needs and desires of the individual in carrying out travel activities. Chi & Pham (2022) explain that travel motivation can affect visit intention. There are several studies have stated that travel motivation can influence the intention to visit a destination (Khan et al., 2018;Hosany et al., 2019;Luo & Ye, 2020;Maghrifani et al., 2021;Zhang et al., 2021). It indicates that motivation in traveling can affect the demand for tourism (Page, 2019) through the formation of the intention to visit a destination. Unlike previous studies, Anggraini & Lupita (2021) found that travel motivation insignificantly affects the intention to visit. From that, it could be indicated that there is a gap in the study about the relationship between travel motivation affecting visit intention. So, the relationship between travel motivation and visit intention will be reviewed in this study based on the existing gap. Fletcher et al. (2017) explain that promotion is essential to build brand and product awareness. Therefore, the existence of promotion of tourism products makes it better known and could influence potential tourists in shaping tourism demand through a tourist experience (Nelson, 2021). Kotler et al. (2021) explain that marketing that has an effect or influence on marketing (such as influencer marketing and celebrity endorsement) has become a popular way of promoting a product, which is usually done by involving the role of social media. An endorser focuses on endorsing or promoting the product, but an influencer tends to engage with the product's consumer (Meena, 2021). However, sometimes celebrities are also often said to be influencers. Nelson (2021) stated that celebrities are classified as 'mega influencers' whose influence can reach many people with a range of followers of more than one million people. Widyastuti (2017) explained that the message in promotions or advertisements is usually persuasive; moreover, it involves trusted and well-known sources making the message more attractive and easier to remember. As a spokesperson or messenger, credibility is essential for a celebrity (Kotler et al., 2021). Therefore, a celebrity must have credibility in his role as an endorser. There are studies about the relationship between celebrity endorser credibility in influencing intention (Song & Kim, 2020;Lili et al., 2022), which indicates that a credible celebrity doing an endorsement can influence the formation of intention (which in tourism is related to intention to visit a destination). So, this relationship will be reviewed too in this study based on the current marketing phenomenon (celebrity endorsement) and the previous studies' findings. Nelson (2021) stated that individuals who can influence (such as influencers and celebrities) could shape attitudes and influence their followers in deciding what is influenced. The decision-making process influenced by the attitude can create an action, for example, in terms of tourism, the demand for tourism to visit. The intention of visiting in tourism is the same as the intention of purchasing (Dewi et al., 2022). Several studies stated that attitudes can influence intentions (Wang et al., 2017;Wang et al., 2020;Lili et al., 2022). In tourism, the intention to visit a destination can be influenced by attitudes toward the destination. The relationship between attitudes that influence visit intentions are also often found in several other studies (Phillips et al., 2013;Huang & van der Veen, 2018;Kim & Kwon, 2018;Rahayu, 2020). So, this relationship will be reviewed in this study based on the previous research's findings. In this study, the attitudes will have an additional mediation role in forming visit intention through relationships with travel motivation and celebrity endorser credibility.
Based on information from the Korean Culture and Information Service (KOCIS), South Korea is known as a country that combines traditional and modern cultures in its tourism (KOCIS, 2020). Tourism has a role as a medium to serve and protect culture (Almuhrzi & Al-Azri, 2018), which according to the Organisation for Economic Cooperation and Development (OECD), it can make destinations more attractive and competitive (OECD, 2009). Currently, a phenomenon of cultural spread originates from South Korea, known as the Korean Wave (Park, 2021). Korean wave (Hallyu) is a term for the phenomenon of widespread South Korean popular culture reaching a global scope to various countries worldwide (Park, 2021), including Indonesia (Nugroho, 2014;Sarajwati, 2020). This phenomenon is spread through things related to the world of entertainment, such as music (K-pop), dramas (K-dramas), movies (K-movies), TV shows that present content about South Korean culture, which now it has covered various other things related to daily life, such as fashion, food (culinary), beauty products (skincare and make-up) to language (Sarajwati, 2020). The Korea Tourism Organization (KTO) has involved Hallyu in its tourism. Seo & Kim (2019) explained that the overall Hallyu or Korean wave effect is found in South Korea's tourism industry. Lim & Giouvris (2020) also stated that the role of Hallyu or the Korean wave in tourism is not ignored. The study explained that there are short-term effects of the Hallyu or Korean wave as an attractive factor for tourist arrivals in South Korea. Through this, the Korean wave phenomenon can have a role and influence South Korea's tourism industry regarding South Korea's popular culture.
In Indonesia, the Korean wave phenomenon is familiar. According to the Korean Foundation for International Cultural Exchange (KOFICE), Indonesia is listed as one of the countries in Asia with high consumption of Hallyu or Korean wave content, along with China, Thailand, Malaysia, and India (KOFICE, 2021). It proves that many Indonesians are interested in and aware of Korean wave things. Interesting in the Korean wave can cause a desire to travel to South Korea by trying to feel the Korean culture directly in South Korea (Ghansiyal, 2021).
Based on data from the Korean Statistical Information Service (KOSIS), the Indonesian citizens who dominated visits to South Korea in 2017-2022 were Indonesian citizens with an age range of 21-30 years, which as many as 185.821 in total five years (KOSIS, 2022). That age range is the range of Generation Z and Millennial Generation. This research will focus on Indonesian citizens, especially Generation Z, as the target respondents, aged 11 -27 years in 2023, with the year of birth 1996 to 2012 (Ananda, 2022). The topic that will be raised in this study is the influence of travel motivation and celebrity endorser credibility on visit intention to South Korea, which involves the mediation effect of tourist attitude, where this research refers to the Korean wave phenomenon in Indonesia. The existence of a gap research study about travel motivation and limited research about celebrity involvement in the topic of endorsement related to marketing and promotion in tourism would be a reason for the researcher to conduct this study further. The researcher also involved the role of tourist attitude as a mediation variable in this study, mediating the relationship between travel motivation and celebrity endorser credibility in affecting the visit intention.
This study contributes to the literature in several ways. First, this study contributes to developing literature on marketing and promoting tourism products and tourist behavior. It is because the topics are celebrity endorser credibility, which is related to promoting and marketing a product, and regarding tourism, travel motivation, attitude, and visit intention, which is related to tourist behavior. The second one is the managerial contribution; this study proposes recommendations for a more effective marketing and promotion strategy for tourism products in South Korea by looking at trends in tourist preferences for travel activity and involving the role of celebrities as endorsers. Some of the literature discussed to draw the aim of the study is mentioned below.

Travel Motivation on Visit Intention
A person's or tourist's needs and wants for a travel activity or things are the meaning of travel motivation (Bhattacharya & Kumar, 2016). Aytas et al. (2021) explain that visit intention is the desire or willingness of a person to visit a destination. The theory of motivation used in this study is Maslow's Motivation Theory, a theory based on the principle of hierarchy or ranking the needs of a person or individual (Page, 2019). The need that creates motivation indicates the existence of a goal to be achieved (in this case, tourist travel activities) (Kotler et al., 2021). Cook et al. (2017) explain that motivation is divided into two; push and pull. In detail, push motivation refers to people's needs and desires for tourist activity, which pushes tourists to travel. Meanwhile, pull motivation relates to the attributes of the destination that attract individuals to visit or can pull tourists into traveling, which is related to the destination's resources.
Regarding tourism, the most relevant travel motivation refers to the cultural aspects (Pung & Del Chiappa, 2018). Cultural aspects closely related to the world of tourism and have elements of uniqueness in it can cause attraction for someone to visit, especially destinations with this culture. Utama (2016) explained that culture, which is included in the attribute part of a destination, can indirectly influence tourists' decisions in determining tourist destinations by the existing role or involvement of the destination image. Therefore, cultural aspects of tourism can affect a person's intention to visit a destination (which culture was part of a destination and part of travel motivation (pull motivation))). It is in line with the study by Chi & Pham (2022) that stated travel motivation can affect visit intention. Several studies also supported the relationship between travel motivation in influencing the intention to visit a destination (Khan et al., 2018;Hosany et al., 2019;Luo & Ye, 2020;Maghrifani et al., 2021;Zhang et al., 2021). The study by Prayag et al. (2018) indicates important factors of travel motives, including escape, learning, novelty, relaxation, self-development, and socialization. Thus, the proposed hypothesis was: H1: Travel Motivation positively and significantly influences Visit Intention

Celebrity Endorser Credibility on Visit Intention
A celebrity figure has a role as a public figure, where his figure is known publicly and identically and can be a role model or idol of a person (Forgeard, 2022). Seeing his figure known publicly, celebrities as public figures are often seen as products, which can be an object that can be marketed (Suwatno, 2017). It is commonly associated with marketing communication, where a celebrity is often used as an advertising model for product marketing (Widyastuti, 2017).
An advertisement in marketing a product is commonly used to build a positive image of a product (Panuju, 2019). Involving a celebrity figure in marketing a product can affect a broad market reach (Nelson, 2021). Celebrity endorser is often used in advertising or promotional things. Schimmelpfennig (2018) explains that a celebrity endorser is a famous personality publicly recognized by name and face. Celebrities as endorsers make it easy for messages from advertisements or promotions to be remembered and attract more attention because they are famous figures (Widyastuti, 2017). Therefore, celebrities as endorsers must have credibility (Kotler et al., 2021). It is to create public trust in the message conveyed. Widyastuti (2017) also explained that the message would be more persuasive if the message given came from a reliable source. So, celebrity endorser credibility refers to the extent of celebrity as an endorser is deemed to have expertise and can be trusted in communicating on certain topics (Goldsmith et al., 2000). The study by Yunita et al. (2021) indicates three things used to measure the credibility of a celebrity endorser; attractiveness, trustworthiness, and expertise. The celebrities in this study referred to celebrities on the Youtube Channel Visit Korea and Imagine Your Korea. Some studies show the relationship of celebrity endorser credibility affects the intention (mostly in purchase intention topic) (Song & Kim, 2020;Lili et al., 2022). From that, the researcher proposed the following hypothesis: H2: Celebrity Endorser Credibility positively and significantly influences Visit Intention

Travel Motivation and Celebrity Endorser Credibility on Tourist Attitude
A motive for traveling is based on the need or desire to be sought to fulfill someone's satisfaction from traveling activities (Page, 2019). Through this goal, an individual is encouraged to carry out an activity related to the individual's behavior based on the individual's attitude. In general, attitude is the way of a person's view and evaluation of something that tends to respond positively or negatively (Vargas-Sánchez et al., 2016). So, tourist attitude may be defined as the way tourists view or evaluation of a destination, related to their behavior which responded, based on their preferences for products and services in the destination (Phosikham et al., 2015;Vargas-Sánchez et al., 2016;Grum, 2021). The existence of travel motivation encourages individuals to carry out travel activities, then can shape the individual's attitude towards these travel activities. That statement was in line with the previous study by Pereira et al. (2019), which states that a person's motivation for traveling can affect a person's attitude. A previous study by Prayag et al. (2018) also stated that travel motivation could positively affect attitude toward the destination. Motivation makes it easier for potential travelers to find the desired travel experience (Nelson, 2021). Thus, the hypothesis proposed was: H3: Travel Motivation positively and significantly influences Tourist Attitude Page (2019) explained that travel motivation is related to the formation of tourism demand. In tourism, marketing promotion can help to form a tourism demand. Such as celebrity endorsement and influencer marketing has become a popular way of promoting a product, which involves the role of social media (Kotler et al., 2021). In their role, a celebrity is also often said to be an influencer, which according to Nelson (2021), classifies celebrities as mega influencers. As an endorser, celebrities or influencers should have credibility (Kotler et al., 2021). In other words, they must be credible in conveying messages related to certain topics in marketing or promotion. Dhun & Dangi (2022) explain that the credibility of influencers influences attitudes positively. Lili et al. (2022) also state that celebrity endorsement or involvement can significantly affect attitudes. Some studies explore the relationship of celebrity endorsers on attitudes (van der Veen & Song, 2013;Wang et al., 2017). This indicates that the credibility of a celebrity or influencer as an endorser can influence attitudes that involve decision-making on matters of effect (Nelson, 2021). Thus, the hypothesis proposed was: H4: Celebrity Endorser Credibility positively and significantly influences Tourist Attitude

Tourist Attitude on Visit Intention
An attitude arises because of the involvement of judgment or evaluation and self-feelings about a thing (Kotler et al., 2021), where the assessment can be positive or negative. Assessments and feelings about destinations and activities can influence attitudes regarding travel and tourism. Destinations as tourist destinations involve the influence of the destination's image (Pereira et al., 2019) or the image of the country (Phillips et al., 2013;Shen et al., 2022) in shaping a person's attitude toward the destination. Whether or not the attitude formed is based on whether or not of someone's view of that destination. Fletcher et al. (2017) stated that attitude was closely related to the image. Sumarwan (2017) explained that attitudes could determine decisions, where attitudes are closely related to a person's behavior and belief in something. The involvement of trust in the destination in shaping someone's attitude from its influence by the image of the destination or country can make someone's attitude towards the destination even better (Shen et al., 2022). The emergence of trust is based on knowledge of the destination as an object of thought, and trust or belief can influence the formation of a person's attitude towards the object (Sumarwan, 2017). Vargas-Sánchez et al. (2016) indicate three dimensions of attitude, that is cognitive, affective, and behavioral. From the literature on tourist attitudes on visit intention, the researcher hypothesized that: H5: Tourist Attitude positively and significantly influences Visit Intention.

The Mediating Effect of Tourist Attitude on Visit Intention
Some previous studies explained the relationship between travel motivation and attitudes that influences (Prayag et al., 2018;Pereira et al., 2019;Happ et al., 2021). Pereira et al. (2019) involve the role of destination image in the influencing relationship between travel motivation and attitude formation. The formation of attitudes is closely related to the image (Fletcher et al., 2017). In addition, Happ et al. (2021) involve the effect of emotional moderation on the relationship between motivation and attitude, where emotions also link to the formation of attitudes, that is, in affective attitudes (Vargas-Sánchez et al., 2016). In addition, several previous studies stated the relationship that influences the celebrity endorser's credibility and attitudes (van der Veen & Song, 2013;Wang et al., 2017;Lili et al., 2022;Dhun & Dangi, 2022). In addition, Lili et al. (2022) also explain that the endorsements of celebrities can influence attitude formation. Through previous studies and explanations, it can be said that the attitude can be influenced by the motivation to travel and celebrity endorsers who have credibility in conveying tourism-related messages in shaping a person's intention to visit a destination. Several previous studies indicate a relationship between attitudes as a mediating role in influencing intentions (Phillips et al., 2013;van der Veen & Song, 2013;Wang et al., 2017;Huang & van der Veen, 2018;Kim & Kwon, 2018;Prayag et al., 2018;L. Wang et al., 2020;Lili et al., 2022). Therefore, this study also formulated the following hypothesis: H6: Tourist Attitude has a role in mediating the relationship between Travel Motivation and Visit Intention H7: Tourist Attitude has a role in mediating the relationship between Celebrity Endorser Credibility and Visit Intention Based on the literature presented, the research model in this study explains the relationship between variables, which that the relationship between travel motivation and celebrity endorser credibility in affecting visit intention with the role of tourist attitude in mediating the relationship. The research model is illustrated in Figure 1.

Method
This research is a causal research design with a quantitative approach. Data collection in this study used purposive sampling techniques where the technique was used with certain restrictions and considerations on its suitability to the topic under study. In determining the number of samples, this study used the determination of the minimum number of representative samples whose determination was based on the number of indicators to be multiplied by 5 . The primary data in this study used questionnaires distributed to the Indonesian Generation Z. The questionnaire collected 385 respondents. The variable measurement scale using Outer Model / Measurement Model Assessment in SEM-PLS data analysis technique, which measures the construct or variable's validity and reliability (can be seen in Table  3). Questionnaire measurement uses an interval scale with a Likert scale as a scaling technique, that is, a Likert scale with five levels, from level 1 (strongly disagree) to level 5 (strongly agree) (Bougie & Sekaran, 2019). In this study, the analysis technique used was Structural Equation Modeling -Partial Least Square (SEM-PLS). SEM-PLS data analysis is a quantitative or statistical analysis technique with a variance-based approach to confirming the relationship and the measurement model ), which will be tested using SmartPLS 4 (Ringle et al., 2022). In this study, there were dependent variables (visit intention), independent variables (travel motivation & celebrity endorser credibility), and mediation variables (tourist attitude), and involved control variables (gender).

Characteristic of Respondents
The respondents in this study were Indonesian Generation Z, aged around 11-27 years in 2023 (with birth years 1996-2012) (Ananda, 2022). The characteristics of the 385 respondents were classified into three things of classification, which that gender, job, and education. The classification can be seen in Table 2 below. Based on the table above, from 385 respondents that have been collected, there were 95 male respondents (24.7%) and 290 female respondents (75.3%). Female respondents dominate the gender classification. The respondent's job was dominated by students/college students, with as many as 316 respondents or as many as 82.1%. Then, the respondents with the senior high school education background dominated, with 246 respondents or as many as 63.9%.

Common Method Bias
In this study, measuring the rate of increase in error in the research data obtained through the questionnaire was necessary. The measurement of the increase in error in this study was seen from the presence or absence of collinearity that occurred in the data using VIF (Variance Inflation Factor) as a measurement test tool . The data is indicated that there is no collinearity if the VIF value is less than 3 (VIF < 3) , so there is no common method bias.

Measurement Model Assessment: Construct Validity
In addition to measuring the presence or absence of collinearity, the next step is to test the validity and reliability of the data obtained. The measurement of construct validity is divided into two types: convergent validity and discriminant validity. Convergent validity is the validity formed when scores from measurements of different instruments on constructs have a high correlation (Bougie & Sekaran, 2019), which is measured or evaluated by considering the outer loading value where the value must be more than 0.70 (outer loading > 0.70). The Average Variance Extracted (AVE) value is where the value must be more than 0.50 (AVE > 0.50) . The discriminant validity will be explained separately.
A reliability test is carried out to determine the stability and consistency of the instrument in its ability to touch variables or research constructs (Bougie & Sekaran, 2019). The reliability test is usually seen through the value of the Cronbach Alpha coefficient, where the value must be more than 0.60 (Cronbach Alpha > 0.60) . Bougie & Sekaran (2019) also stated that if the value of the resulting Cronbach Alpha coefficient was high, the instrument measurement was good. In addition, Composite Reliability can also measure the reliability of a research instrument as well as the Cronbach Alpha. Composite reliability must have a value of more than 0.70 (Composite Reliability > 0.70) . The result of the convergent validity and reliability test is shown in Table 3.   . It indicates that the indicators on the data are valid and highly correlated because the value of the outer loading was more than 0.7 (> 0.7), and the AVE value was more than 0.5 (> 0.5) (Bougie & Sekaran, 2019). In addition, the reliability of the data can be seen through the values of Cronbach Alpha and Composite Reliability . Cronbach's alpha scores of travel motivation, celebrity endorser credibility, tourist attitude, and visit intention were 0.976, 0.955, 0.946, and 0.899, respectively. Then, the Composite Reliability values are 0.978, 0.960, 0.952, and 0.921, respectively. Both measurement results indicate that the data are consistent in touching the research variables, where the value of Cronbach's alpha produced is more than 0.6 (> 0.6), and the Composite Reliability value is more than 0.7 (> 0.7) . Then the data obtained is indicated to be reliable.

Discriminant Validity
As mentioned before, the measurement of construct validity is divided into two types; convergent and discriminant. Discriminant validity is formed when constructs are predicted to have a low degree of correlation or are not correlated with other constructs (Bougie & Sekaran, 2019). The measurement of the discriminant validity is with HTMT (Heterotrait-Monotrait Ratio), where the value must be less than 0.90 (HTMT < 0.90) . As shown in Table 4, the obtained value of HTMT (Heterotrait-Monotrait Ratio) of all constructs is less than 0.90, indicating that all of the constructs used are not correlated with other constructs and are discriminantly valid .

Structural Model Assessment: Hypotheses Testing
After measuring the outer model and the measurement has met the requirements and rules, proceed with the inner model measurement. Inner model measurement evaluates structural measurements to test the significance of predictive relationships between variables or constructs . This measurement tests existing hypotheses through the Bootstrapping procedure in SmartPLS 4, which can obtain path coefficients and t-values. Path coefficients are used to determine the positive-negative relationship between constructs where the measurement is indicated to have a positive relationship if the value of the path coefficients is less than 0.05 (< 0.05), and the significance level is 5% (Hair et al., 2023). Meanwhile, the value of t-values is a value used to determine the degree of significance in the relationship between constructs whose measurements are identified as having a significant relationship if the value of the t-values is more than 1.645 (> 1.645) with a 1-tailed test (Hair et al., 2023). The results of hypothesis testing can be seen in Table 5.  Table 5, it can be indicated that all these hypotheses have a positive relationship because the path coefficient value is less than 0.05 (< 0.05) (Hair et al., 2023). In addition, the resulting t-values on the relationship of all hypotheses are more than 1.645 (> 1.645), which indicates that all hypothesis relationships have a significant relationship (Hair et al., 2023). The results showed that travel motivation positively and significantly influenced the intention to visit South Korea (p-values = 0.000, t-values = 5.721). Then, the credibility of celebrity endorsers also has a positive and significant effect on visiting intentions (p-values = 0.000, t-values = 4.289). Therefore, H1 and H2 are accepted.
In addition, this study's results also show a positive and significant relationship between travel motivation affecting tourist attitudes, which is that the Indonesian Generation Z toward South Korea as a tourist destination (p-values = 0.000, t-values = 7.070). The results also showed a positive and significant relationship between the credibility of South Korean celebrities in their role as endorsers for South Korean tourism and the attitudes of the Indonesian Generation Z tourists in South Korea (p-values = 0.000, t-values = 8.296). In addition, this study also shows that tourist attitudes towards South Korea as a tourist destination have a positive and significant effect on the intention to visit South Korea by the Indonesian Generation Z (p-values = 0.000, t-values = 7.877). Then, H3, H4, and H5 in this study are accepted.
In addition, the study also involved a mediating role of tourist attitudes in the relationship between travel motivation and visit intention and the relationship between celebrity endorser credibility and visit intention. The results show that the attitudes of the Indonesian Generation Z as tourists have a positive and significant influence in mediating the relationship between travel motivation and their intention to visit South Korea (p-values = 0.000, t-values = 5.005). The results of this study also shows that the attitude of the Indonesian Generation Z as tourists has a positive and significant influence in mediating the relationship between the credibility of South Korean celebrities in their role as South Korean tourism endorsers (concerning the Korean wave / Hallyu phenomenon) in shaping the intention of the Indonesian Generation Z to visit South Korea (p-values = 0.000, t-values = 5.716). Therefore, H6 and H7 in this study are supported and accepted. The result on the relationship of the control variable was also supported and accepted (pvalues = 0.041, t-values = 1.740), which explains that gender positively and significantly affects the dependent variable (endogenous construct), visit intention.

Coefficient of Determination (R 2 Value)
The measurement of the inner model is also seen from the R 2 value in the exogenous construct (independent variables and mediation variables) to their substantial influence on the endogenous construct (mediation variables and dependent variables).  explain that the model can be said to be weak, moderate, and strong if the identification of R 2 values of 0.25, 0.50, and 0.75. In addition, the result of the R 2 value indicates the value of the predictor construct, which explains that the high value of the R 2 value produced is based on the high value of the predictor construct . In this study, the R 2 value of Visit Intention is 0.579. Therefore, 57.9% of variances in the Visit Intention are determined by Travel Motivation, Celebrity Endorser Credibility, and Tourist Attitude. In other words, 42.1% of the variances are determined by other factors that are not included in this model study. Besides that, there is another exogenous variable which is tourist attitude. The R 2 value of Tourist Attitude is 0.440. Therefore, 44% of variances in Tourist Attitudes are determined by Travel Motivation and Celebrity Endorser Credibility. In other words, 56% of the variances are determined by other factors that are not included in the model. So, based on the R 2 values, it can be said that the model in this study is classified as moderate on average.

Effect Size (f 2 Value)
The f 2 value shows the contribution effect of the exogenous construct on the endogenous construct. The identification of f 2 values of 0.35, 0.15, and 0.02, respectively, indicates that the contribution effect of the exogenous construct on the endogenous construct is large, medium, and small . There are two endogenous constructs in this study; tourist attitude and visit intention. In a relationship on tourist attitude as an endogenous construct, there are travel motivation and celebrity endorser credibility as an exogenous construct that affects it with the result of the f 2 value were 0.143 and 0.252, respectively. Travel motivation and celebrity endorser credibility have a medium effect on tourist attitude. In addition, the visit intention as an endogenous construct has a relationship with travel motivation, celebrity endorser credibility, and tourist attitude, and also by gender, which the result of f 2 values were 0.115, 0.076, 0.195, and 0.08, respectively. It indicates that the effects were medium, small, medium, and small, respectively.

Predictive Relevance (Q 2 Value)
The Q 2 value was an assessment of the predictive power of the out-of-sample model or the relevance of predictive using the blindfolding procedure . The assessment applied to endogenous construct, which in this study were tourist attitude and visit intention. The Q 2 value indicates there is the relevance of predictive if the value is enormous or more than 0 (Q > 0) . The indication of the relevance of predictive value (Q 2 value) was the same as the f 2 value, which indicates large, medium, and small predictive power of endogenous constructs with the Q 2 value of 0.35, 0.15, and 0.02, respectively . From the result of this study, the Q 2 predicted value of each indicator was more than 0. It indicates that there is the relevance of predictive on endogenous constructs. Most of the indicators in the PLS-SEM analysis yields, which the analysis yield contains RMSE and MAE, have more minor prediction errors than the LM analysis yields. Then, it indicates that the model has a medium predictive power.

Discussion
Researchers use travel motivation and the South Korean celebrity endorser credibility to understand the intention of Indonesians visiting South Korea, especially the Indonesian Generation Z. In addition, researchers involve tourist attitudes as 'bridging' these influences in shaping the Indonesian Generation Z's intention to visit South Korea. It is attributed to South Korea's tourism promotion marketing, which has involved the Korean wave phenomenon in its tourism, so celebrity involvement is often seen in South Korean tourism promotion. The involvement of the Korean wave (Hallyu) in South Korean tourism is one of the effective marketing strategies in affecting the image maker of South Korea, which is related to someone's perspective or point of view about South Korea itself. Bang et al. (2021) explained that K-pop, as part of the Korean wave, positively affects the Korean image generally. Chae et al. (2020) also stated that K-drama, as part of the Korean wave, positively influences attitudes toward K-drama, which affects the Korean image nationally. Those indicate that as part of the Korean wave, K-pop and K-drama are contributing to forming the image of South Korea as pop culture. The image of a destination can strengthens the travel motivation in making a form of intention to travel to that destination (Chi & Pham, 2022).
Based on the results of this study, travel motivation, and celebrity endorser credibility have a positive and significant effect on visit intention to South Korea. It indicates that a travel motivation from the Indonesian Generation Z influences his intention to visit South Korea. It is explained that the better and stronger motivation to travel to South Korea and the better and stronger the credibility of celebrities in endorsing Korean tourism products, the better and stronger the intention to visit South Korea. This study supports the results of several previous studies that suggest the relationship between travel motivation and visiting intentions (Khan et al., 2018;Hosany et al., 2019;Luo & Ye, 2020;Maghrifani et al., 2021;Zhang et al., 2021). Knowing and understanding the motivation that drives people to visit a destination will be better in forming and increasing the intention to visit a destination. Besides that, it will be more effective for doing a promotional campaign or marketing tourism products, so the goal of forming the intention to visit can be pursued effectively. Even more, the involvement of a celebrity as an endorser can help the promotional campaigns and the marketing of tourism because it can be an influential factor that attracts the intention of tourists to travel to a destination. From the results, it was explained that the credibility of South Korean celebrities in endorsing South Korean tourism (where the celebrity in question is a celebrity involved in South Korean tourism promotion content) could influence the formation of Indonesian Generation Z's intention to visit South Korea. The result of this study is consistent with Rahmi et al. (2017), which indicates that the celebrity is better at forming an intention to purchase a product (the study discussed beauty products). It is in line with van der Veen & Song (2013) that the celebrity endorser significantly affects the forming of visit intention. A similar influence was also found in certain studies that stated a relationship between celebrity credibility on the formation of purchase intentions (Song & Kim, 2020;Lili et al., 2022). Studies by Dewi et al. (2022) explain that purchase intention can be likened to the intention to visit. It is because both things form an intention to buy a product, where tourism is related to tourist visits. So, in making a form of visiting intention to South Korea through tourism promotion and marketing, it must be better if considering the motivation to travel and the involvement of a credible celebrity as an endorser.
In addition, the results also indicated that travel motivation and celebrity endorser credibility have a positive and significant effect on the tourist attitude of South Korea as a tourist destination. That explained that favorable travel motivation and favorable credibility of celebrities in endorsing the product would make favorable attitudes of tourists toward South Korea as a tourist destination. It is consistent and supports the previous studies, which stated that motivation positively impacts an attitude toward a destination (Prayag et al., 2018;Pereira et al., 2019;Happ et al., 2021). In forming a favorable attitude of tourists toward a destination, which is South Korea, it would be good to increase the favorable motivation that drives people to visit South Korea. For example, the Korean wave phenomenon spread globally and involved South Korean tourism. People motivated by the Korean wave may develop a positive attitude of tourist toward a destination by offering K-drama site or K-pop sites on the activity like visiting the filming sites of K-drama, wearing Hanbok, which is the traditional clothes of South Korean culture or visiting entertainment agencies and K-Star Road in Gangnam. These results support several previous studies that stated a positive and significant relationship between the credibility of celebrity endorsers and attitudes (van der Veen & Song, 2013;Wang et al., 2017;Lili et al., 2022;Dhun & Dangi, 2022). In endorsing a product, the celebrity must have credibility (Kotler et al., 2021). Celebrity endorsement is the relay of the communication of a product or brand (Halder et al., 2021), so it must have credibility in endorsing and influencing others, which can form people's attitudes toward the product. For example, BTS, as one of the K-star now used in tourism promotion in South Korea, can attract people's attention toward South Korea. It makes people aware of South Korea as a tourist destination that could be visited later.
The results of this study also indicate that tourist attitudes positively and significantly affect the intention to visit South Korea. It is explained that the more favorable the tourist attitude formed toward South Korea, the more favorable the intention to visit South Korea. It supports previous studies that indicated a relationship between attitudes influencing visiting intentions (Phillips et al., 2013;Kim & Kwon, 2018;Huang & van der Veen, 2018;Rahayu, 2020). Besides that, several studies state the relationship between attitudes and intention (Wang et al., 2017;L. Wang et al., 2020;Lili et al., 2022). It would be a good thing to increase the favorable attitude of tourists toward the destination in making a better intention to visit South Korea. For example, the study of Tahira (2022) talks about Muslim-Friendly and Halal Tourism in South Korea; a positive attitude was formed in recommending Muslim-Friendly places in South Korea, so it could make a positive intention of others that were recommended to visit South Korea. The results of this study also indicated the mediation role of tourist attitude in positively and significantly mediating the relationship between travel motivation and visit intention and between celebrity endorser credibility and visit intention. In line with this, Prayag et al. (2018) stated that motivation significantly affects the attachment to places and positively affects overall attitudes, which are significant predictors of the intention to recommend. In that study, the overall attitude mediated the relationship between motivation and intention to recommend. Hosany et al. (2019) also state that motivation and place attachment are vital to determining the intention to visit a place or destination. In addition, Pereira et al. (2019) stated that travel motivation can positively and significantly influence tourist attitudes toward destinations. Then, the study by Lili et al. (2022) explains that celebrity endorsements have a positive and significant indirect relationship to purchase intention by involving attitudes to mediate the relationship (where the study discusses brands). So, the tourist attitude formed is a media in bridging the effect of travel motivation and celebrity endorser credibility on visit intention to South Korea.

Conclusion
This study shows the relationship between travel motivation and the credibility of celebrity endorsers in influencing the intention of visiting South Korea, which involves a mediating role by tourist attitudes. This study focuses on Indonesian Generation Z as the object of research. The results showed that the travel motivation and credibility of South Korean celebrities in endorsing South Korean tourism (where the celebrity in question is a celebrity involved in South Korean tourism promotion content) could influence or contribute to the formation of the Indonesian Generation Z's attitude toward South Korea as a tourist destination and intention to visit South Korea. The study results also state that tourist attitude towards South Korea has a positive and significant influence on the intention of the Indonesian Generation Z to visit South Korea. Tourist attitude also mediates the relationship between travel motivation and celebrity endorser credibility in affecting the visit intention to South Korea. Gender as a control variable also affected the visit intention. This study contributes to developing literature on marketing and promoting tourism products and tourist behavior literature.
Based on the results obtained, practical implications can be suggested and contributed to certain parties. This study contributes to Korean Tourism Organization (KTO) for South Korean tourism's marketing and promotional campaigns. Travel motivation and celebrity endorser credibility could influence the tourist attitude and the intention to visit South Korea as a tourist destination. Therefore, we suggest packaging the promotional contents of South Korean tourism about the destinations or attractions by involving the role of South Korean celebrities as an endorser, either an actor/actresses or a member of a South Korean idol group, in making awareness of South Korean tourism products and forming an intention to visit South Korea. It can help the promotion and marketing of South Korean tourism products to be more effective. The promotional content of that package must include fun travel activities so it looks attractive to tourists and triggers motivation for traveling to South Korea. The study also contributes to travel agencies in Indonesia (or other countries) with the outbound tour to South Korea. Based on the finding, we suggest understanding the needs and wants of tourists as a market and also seeking the travel trends to South Korea in making tour packages to South Korea. In increasing Indonesian Generation Z's motivation to South Korea, besides travel trends to South Korea, travel agencies should be aware and know their preferences of them in the context of travel to South Korea. The products would be effective in pursuing the marketing and sales goal.
This study is limited to its variables which only involve travel motivation and celebrity endorser credibility as independent variables, visit intentions as dependent variables, and tourist attitude as mediating variables that can act as dependent and independent variables, and also involve control variables which are gender. This study is limited to the Indonesian Generation Z as the object or target respondent. For future research, research can be developed by adding other variables and increasing the number of respondents to expand the scope of the study, or it can also be done by changing existing variables with other suitable variables.