South Korean Capital Market Reacts to Park Ji Min's Solo Debut

The author(s) declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Introduction
Companies listed under K-pop music and in the Korean capital market are among the investment alternatives for the public, especially K-pop fans.(Azzahra et al., 2022).HYBE Corporation is one of the companies that mainly focuses on K-pop.The company was officially listed on the Korea Stock Exchange under Big Hit Entertainment on October 15, 2020.It raised 963 billion KRW in its initial stock offering on the Korea Stock Exchange, making it the largest IPO in South Korea in the last three years.Shares opened at 270,000 KRW -double the IPO price of 135,000 KRW -and closed at 258,000 KRW.These figures brought the company's valuation to KRW 8.7 trillion (Cirisano, 2020).HYBE Corporation's share price was observed to increase until it peaked on November 18, 2021, at KRW 419,000.Source: finance.yahooHYBE Corporation's shares recorded a 27.5% drop in early trading on June 15, 2022, to 168,000 KRW after closing at 193,000 the previous day.Within the first hour of trading, the stock fell to 140,000 KRW, losing approximately $1.7 billion in total market capitalization before returning to a price of 145,500 KRW.HYBE shares ended the day down 24.9% to 145,000 KRW. Rachmawati (2022) suggests that on September 28, 2022, HYBE Corporation again recorded a 7.1% decline in share price.At that time, HYBE Corporation shares were traded for 129,000 KRW.The price is lower than the initial public offering (IPO), recorded at 135,000 KRW.The decline in HYBE Corporation's share price was noted to have begun after the announcement that BTS, one of its boy groups, would go on hiatus and focus on individual activities.One of the BTS members who released solo works during BTS' hiatus period is Park Ji Min, who has had a considerable influence in the entertainment industry.On January 16, 2023, French luxury brand Dior introduced Ji Min as a global ambassador.This caused Dior's share price to skyrocket to an all-time high.The share price rose to 775.50 EUR on the same day.On January 18, 2023, the share price rose to 789.00 EUR, reaching a 31-year high.This shows that each member can individually develop their branding power (Diderich, 2023).Issues and news about an idol can affect the stock price of related music companies (Chofifah & Suryani, 2022).The market size of South Korea's entertainment industry continues to grow, and the popularity of K-pop is increasing globally (Messerlin & Shin, 2013).Investing in K-Pop-related companies can be a promising opportunity, but thorough research and analysis of individual companies and market trends are essential to making informed investment decisions.Abnormal return refers to changes in a company's stock price that general market factors cannot explain.This abnormal return can be an unexpected increase in stock price or an unanticipated decrease.At the same time, beta risk plays a vital role in measuring the impact of events on stock prices.Companies with high beta tend to be more susceptible to price fluctuations during certain events, whereas companies with low beta may be less affected.
This study refers to research by Soraya, (2023) entitled "An Event Study: Indonesian Capital Market Reaction to The Russia-Ukraine War Announcement."This study examined differences in abnormal return variables and found no significant differences between abnormal returns before and after the announcement of the Russia-Ukraine war.This aligns with the opinion of (Bahri & Fatchurrohman, 2023).Bahri & Fatchurrohman, (2023) in their research, "Capital Market Reaction to the Announcement of the Prohibition of Syrup Drug Distribution," and (Hotimah & Astawinetu, 2020) through the results of the study "Analysis of Differences in Stock Returns and Abnormal Returns Before and After the Protest from Greenpeace About Plastic Waste at PT. Unilever." The results, which suggest that there is no difference in abnormal return value, contradict the research of Yousaf et al. (2022) on "The reaction of G20+ stock markets to the Russia-Ukraine conflict "black-swan" event: Evidence from event study approach" with the results of abnormal returns before and after the launch of 'special military operations' by Russian military forces showing a strong negative impact of this military action on most stock markets, which means there are differences in these variables.Machfudi & Isynuwardhana (2023), in their research "Analysis of Capital Market Reaction to the Russian and Ukrainian War Events (Case Study on Shares of Energy Sector Companies Listed on the Indonesia Stock Exchange)" also obtained the results that there were significant differences in abnormal returns before and after the events of the Russian and Ukrainian wars.
In addition to the abnormal return variable, some previous studies used the stock price variable.Research by Lubis et al., (2023) in "Analysis of The Capital Market Reaction to The Announcement of The Stock Split" indicates that stock prices are significantly affected before and after the announcement.Cung & Rakhmat (2022), in a study entitled "Are There Differences in Stock Prices, Trading Volume, Abnormal Return Between Before and After the Merger of PT Indosat?" supports the statement that there are significant differences in stock prices before and after an event.Research by Pardiansyah et al. (2023) entitled "Comparative Analysis of Sharia Stock Prices and Returns in the Health Sector Before and During the Covid-19 Pandemic" suggests that stock prices do not experience significant differences both before and during the Covid-19 pandemic.The last variable is a beta risk;  2021) obtained the results that there is a significant risk difference between before and during the COVID-19 pandemic in Indonesia.
Based on existing research, this study will also look at the stock market reaction based on another event, namely Park Ji Min's solo debut.This study will focus on three variables, namely abnormal return, stock price, and beta risk, to test whether the solo debut of Park Ji Min, an artist who is a boy band personnel with international popularity, will impact the movement of HYBE Corporation shares.The difference between this study and previous studies lies in the combination of variables used, the method of measuring beta risk, and the events studied, and will only focus on one company.

Stock
Stock price refers to the value of a share of stock traded on a stock exchange at a specific point in time, determined by the supply and demand dynamics in the market (Azis & Hartono, 2017).It represents the market's consensus on a company's equity value at any given moment.Generally, stock price refers to the closing price during the observation period for each stock included in a sample, and it is closely monitored by investors (Pardiansyah et al., 2023).The movement of stock prices is paramount to investors, as it provides critical insights into the market's perception of a company's performance and prospects.In the capital market, stock prices are categorized into three main types: the highest price (high price), the lowest price (low price), and the closing price (close price).These prices reflect a stock's trading activity range during a trading session and serve as critical indicators for investors and analysts.The highest price represents the maximum price at which a stock was traded during the day, while the lowest price indicates the minimum price.The closing price is particularly significant, as it represents the final trading price for a stock at the end of a trading session and is often used as a benchmark for evaluating stock performance (Ta et al., 2020).
Understanding stock prices is crucial for investors because it directly influences investment decisions and portfolio management strategies.The fluctuations in stock prices are influenced by various factors, including company performance, macroeconomic indicators, market sentiment, and external events such as geopolitical developments or major corporate announcements (Baker, 2024).As stock prices are closely tied to the perceived value of a company, they also play a critical role in determining shareholder wealth and market capitalization (Parveen & Siddiqui, 2017).Recent studies have emphasized the importance of analyzing stock price movements to predict market trends and assess risk (Zakhidov, 2024).For example, a study by Katembo (2024) highlighted the impact of market volatility on stock price fluctuations, suggesting that investors should carefully monitor these movements to mitigate potential risks.Haritha & Uchil (2020) explored the relationship between stock prices and investor behavior, finding that changes in stock prices significantly influence investor sentiment and decision-making processes.

Abnormal Return
Abnormal return is commonly used to test market efficiency and typically occurs around the announcement of a significant event.The magnitude of abnormal returns can vary depending on the relative size of the event and the overall market conditions (Alves & Silva, 2021).A market is considered efficient when no investors experience abnormal returns, meaning all available information is fully reflected in stock prices (Andriansyah & Irwandi, 2023).Positive abnormal returns indicate that the actual return exceeds the expected return anticipated by investors, suggesting that the market has reacted favorably to the event (Santoso & Silitonga, 2023).Conversely, negative abnormal returns occur when stock prices decline significantly following an event, resulting in lower returns than investors expected.
Positive or negative abnormal returns are critical in investment decisions, as these returns can signal the market's reaction to specific events and have significant implications for stock prices and liquidity.For instance, a positive abnormal return may encourage investors to increase their holdings, anticipating continued positive performance.On the other hand, a negative abnormal return might prompt investors to sell off their shares to avoid further losses, potentially leading to decreased liquidity and downward pressure on the stock price (Linnainmaa & Zhang, 2021).Understanding the dynamics of abnormal returns is essential for investors seeking to navigate market fluctuations effectively.Research has shown that abnormal returns are not only indicators of market reaction but also provide insights into the market's overall efficiency.For example, Dewi et al., (2022) found that abnormal returns are closely tied to market sentiment and can reflect broader economic trends.Similarly, Linnainmaa & Zhang, (2021) emphasized the importance of analyzing abnormal returns to assess the potential impact of significant events on stock performance.Shleifer (2000) highlighted that abnormal returns often serve as early indicators of market inefficiencies, allowing investors to adjust their strategies accordingly.

Risk
Risk is a form of uncertainty related to future situations that may arise due to decisions made based on different considerations today.In the context of investment, risk can be understood as a measure of the potential loss that may occur during investment activities.Accurately predicting the level of risk in investments is crucial for minimizing possible losses and optimizing returns by leveraging trends and changes in influential variables (Puspitaningtyas, 2015).Investment risk is inherently tied to the uncertainty surrounding the future performance of assets, making it a fundamental concept in financial analysis.The ability to anticipate and manage risk effectively is essential for investors who seek to balance the trade-off between risk and return.By understanding the factors influencing risk, investors can make informed decisions aligning with their financial goals and risk tolerance (Sivarajan, 2019).For example, predicting risk in a volatile market allows investors to adjust their portfolios to protect against significant losses while pursuing potential gains.
Several studies have emphasized the importance of risk prediction and management in achieving successful investment outcomes.For instance , Hampton, (2009) highlights that accurately assessing risk can lead to better investment strategies, enabling investors to identify and capitalize on market opportunities while avoiding potential pitfalls.Similarly, Maginn et al., (2007) argue that understanding risk is about avoiding losses and optimizing returns by strategically positioning investments in response to market dynamics.The relationship between risk and return is a central tenet of modern portfolio theory, which posits that higher levels of risk are associated with the potential for higher returns (Constantinides & Malliaris, 1995).However, this relationship also underscores the importance of risk management, as investors must carefully weigh the potential rewards against the possibility of significant losses.Thompson & Walker, (2021) noted that effective risk management involves diversifying investments, analyzing market trends, and staying informed about macroeconomic factors that could impact asset performance.

Park Ji Min's Solo Debut
In 2023, Ji Min released her first album, "FACE."The album depicts Ji Min facing herself and how she prepared herself as a new soloist.(Suteja, 2023).The album ranked number 2 on the Billboard 200 chart, with album sales of 124,000 units, marking the third biggest sales week in 2023 and the biggest for a solo artist this year."FACE," which is mainly performed in Korean, consists of six tracks: "Face-off," "Interlude: Drive," "Like Crazy," "Alone," "Set Me Free, Pt. 2," and "Like Crazy (English Version)."The song "Like Crazy" in the album made Ji Min the first South Korean solo artist to top the Billboard Hot 100 chart."Like Crazy" broke 254,000 combined total downloads of the song and CD single, attracting 10 million views and 64,000 radio broadcasts in its first week.(Trust, 2023).
Park Ji Min's solo debut can be used as a reference or signal to investors when deciding, especially for HYBE Corporation shares as a company with a work contract with her.This research will observe HYBE Corporation's stock performance before and after Park Ji Min's solo debut as measured through abnormal return, stock price, and beta risk variables.This research will also find out whether there are differences in these variables within a predetermined period.

Changes in Abnormal Return Before and After Park Ji Min's Solo Debut
The critical variable in this hypothesis is abnormal return, which is the difference between a stock's actual and expected returns over a specific period.Abnormal return is used to evaluate the impact of events on a stock's market value, such as a product launch, financial announcement, or, in this case, the solo debut of a famous artist.Understanding abnormal returns is essential in financial analysis, providing insights into market reactions to significant events.Measuring abnormal returns for Park Ji Min's solo debut helps gauge how the market, including investors and fans, reacts to this debut.This research is crucial as it can demonstrate how a high-profile solo debut, in collaboration with the entertainment agency, influences the company's stock value.The hypothesis posits that there is a change in abnormal returns before and after Park Ji Min's solo debut.This is based on the idea that the debut is a significant event likely to affect market sentiment and investor expectations, leading to fluctuations in stock prices.Whether the sentiment towards the debut is positive or negative, it is expected to be reflected in the changes in abnormal return.
Several studies support this hypothesis.Cung & Rakhmat (2022) found that significant events in the entertainment industry, including artist debuts, often result in notable changes in the abnormal returns of related companies' stocks.Chofifah & Suryani (2022) also highlighted how celebrity-related events directly impact investor behavior and market performance.Lubis et al. (2023) observed significant abnormal returns surrounding the debut of K-pop artists, indicating strong market reactions.Machfudi & Isynuwardhana (2023) similarly identified shifts in abnormal returns to solo debuts, underscoring the importance of assessing market responses to major entertainment events.
H 1 : There is a Change in Abnormal Return Before and After Park Ji Min's Solo Debut.

Stock Price Before and After Park Ji Min's Solo Debut
The primary variable in this hypothesis is the stock price, which refers to the market value of a share traded on a stock exchange.Stock prices are influenced by company performance, economic conditions, and specific events that can affect market perceptions of a company's value.In this context, the stock price is used to assess the impact of Park Ji Min's solo debut on the associated company's value.The stock price is vital in the financial market analysis as it reflects a company's value and investor perceptions.Analyzing changes in stock prices before and after a significant event like Park Ji Min's solo debut offers insights into market reactions, which are crucial for making informed investment decisions.Understanding how such events influence stock prices helps investors and financial managers navigate market dynamics more effectively.
The hypothesis suggests a significant change in stock price before and after Park Ji Min's solo debut.This is based on the idea that the debut, being a highly anticipated event, can affect market perceptions and, consequently, the stock price of the related company, such as the entertainment agency managing the artist.Positive market reactions may increase stock prices, while adverse reactions could result in a decline.Thus, the hypothesis assumes that stock prices will fluctuate in response to the debut.Empirical evidence from previous studies supports this hypothesis.Lubis et al. (2023) found that K-pop artist debuts often trigger significant changes in stock prices before and after the event.Cung & Rakhmat (2022) similarly observed that significant events in the entertainment industry, including artist debuts, cause substantial fluctuations in stock prices.Wicaksono, (2022) also reported that essential announcements or events significantly impact stock prices, indicating market sensitivity to such occurrences.The key variable in this hypothesis is beta risk, a measure of a stock's systematic risk relative to the overall market.Beta indicates how sensitive a stock's price is to market fluctuations, with values greater than 1 suggesting higher volatility than the market and values less than 1 indicating lower volatility.In this study, beta risk is analyzed to assess how the risk associated with a company's stock changes before and after Park Ji Min's solo debut.Beta risk plays a crucial role in investment analysis, as it provides insights into the level of risk a stock carries compared to the market.Investors rely on beta to evaluate the potential risks and returns in their portfolios.Understanding how beta risk varies before and after a significant event, such as Park Ji Min's solo debut, can help investors determine if a stock becomes more or less risky due to the event.This is crucial because shifts in beta can affect investment decisions, risk management, and asset allocation.
The hypothesis suggests that beta risk changes before and after Park Ji Min's solo debut.The reasoning is that this debut, as a significant event in the entertainment industry, could influence investor perceptions of the associated company's stock risk.If the debut is seen as a potential volatility trigger, the stock's beta risk may rise, indicating increased systematic risk.Conversely, if the debut reduces uncertainty, the beta risk may fall, reflecting decreased risk.Thus, the hypothesis anticipates a change in beta risk as a response to the debut.

Research Design and Methodology
This study's research approach is quantitative, using secondary data.It also uses the event study research type to study market reactions to information from certain announcements or posts.

Source: data processed, 2023
The research conducted is development research, which is a form of research that adds new variables and indicators.In this case, researchers used a different hypothesis test for the beta risk variable, the single index model regression technique, and chose a different research object from previous studies, Park Ji Min's solo debut.This research is located at the Korea Stock Exchange (KRX) or the South Korean Stock Exchange.
The population used in this study is the entire HYBE Corporation stock listed on the Korea Stock Exchange (KRX) before and after Park Ji Min's solo debut.The sample of this study was obtained through a time series sampling technique that allows researchers to collect stock price data within a specified time interval, with a total of 60 days consisting of 30 days before and 30 days after Park Ji Min's solo debut.This research uses time series sampling techniques.Time series sampling refers to the process of collecting and analyzing data points collected over some time.The data collection method applied in this study is documentation by identifying news about Park Ji Min's solo debut  Valid N (listwise) 30

Findings Descriptive Statistical Analysis Test
Descriptive statistics provide an initial description of the research variables and are used to determine the characteristics of the samples used in the study.Based on Table 1, the abnormal return on HYBE Corporation shares before Ji Min's solo debut has a minimum value of -0.05829, a maximum value of 0.06351, an average (mean) of -0.0002773 and a standard deviation of 0.02940954.At the same time, the abnormal return on HYBE Corporation shares after Ji Min's solo debut has a minimum value of -0.05106, a maximum value of 0.8941, an average (mean) of 0.0122667, and a standard deviation of 0.03045873.Table 2 shows the stock price of HYBE Corporation before Ji Min's solo debut, which has a minimum value of 173,500, a maximum value of 202,000, an average (mean) of 185,580, and a standard deviation of 6430.123.At the same time, The HYBE Corporation stock price after Ji Min's solo debut has a minimum value of 182,100, a maximum value of 294,500, an average (mean) of 237763.33,and a standard deviation of 36824.687.When viewed from the share price before 202,000 and after 294,500, this shows a reaction shown by investors from before to after Ji Min's solo debut, which is indicated by a significant increase in share price.The table of data normality test results for the stock price variable above shows that the stock price showed a significance level of 0.2 for the stock price before Ji Min's solo debut, which means it is greater than the profitability value of 0.05 and shows a significance level of 0.034 for the stock price after Ji Min's solo debut, which means it is smaller than the profitability value of 0.05.These results suggest that Ho is rejected or implies that the data is not normally distributed.These results mean Ho is denied, or the data can be interpreted as not normally distributed.Based on the paired sample t-test, as shown in Table 5, it is known that the mean value or average change in the abnormal return variable in the period before and after Ji Min's solo debut is -0.01254400.The standard deviation value of 0.03551606 indicates the variation in the data difference in the relevant period.In contrast, the value of 0.00648432 in the standard error of the mean illustrates how accurately the sample average represents the actual average of the population related to abnormal returns.The 95% Confidence Interval of the Difference value estimates the exact value of the difference between the two periods being compared in the interval -0.02580591 to 0.00071791.The t-statistic value of -1.935 indicates how far the sample mean is from zero, with degrees of freedom (df) of 29 indicating how much data was used to calculate the value.The value of -1.935 suggests that the difference between the two periods is lower than expected on average, which could mean a decrease or lower change in the period after Ji Min's solo debut.On the significance side, the one-sided p-value is 0.031, indicating a significant difference in abnormal returns, while the twosided p-value is 0.063, indicating a tendency for a difference but with a slightly lower significance level.
Referring to the test results table 6, it is scientifically proven that HYBE Corporation experienced changes in stock prices during the study period.The hostile ranks column indicates two stock price data after Ji Min's solo debut that are smaller than the previous period, with a mean of 3.00 in an amount of 6.00, which illustrates the difference in stock prices after Ji Min's solo debut is lower than before.On the other hand, in the positive ranks column, it is known that there are 28 stock price data after the event that is greater than the period before Ji Min's solo debut, with a mean of 16.39 in an amount of 459.00, which indicates that the stock price after Ji Min's solo debut is higher than before.The ties column shows no similarity in stock prices during the specified period.
Table 7 provides the Z value, which shows a significant difference between the two conditions.The number -4.659 in the column indicates an extreme difference in stock prices between the two periods.The value of Asymp.Sig.(2-tailed) smaller than 0.001 suggests that the p-value is smaller than 0.001.This indicates that the observed difference between the two conditions is statistically significant.The beta coefficient for the Korea Composite Stock Price Index (KOSPI) is 1.820.The positive and statistically significant beta coefficient with a p-value of 0.002 indicates that HYBE Corporation's stock reacted highly to overall market movements before Ji Min's solo debut.It can be seen that before the event, HYBE stock price trends tended to follow the flow of significant changes in the KOSPI index, confirming the existence of a close relationship between market trends and the company's stock performance during this period.This means that HYBE Corporation's stock returns tend to be sensitive to changes in the KOSPI index.The significance value of 0.002 also indicates that KOSPI movements had an essential influence on HYBE Corporation's stock returns before Park Ji Min's solo debut.The analysis results show a relatively low beta coefficient for HYBE Corporation shares after Park Ji Min's solo debut, which is 0.133.This value indicates that HYBE Corporation stock returns in the period after Ji Min's solo debut have low sensitivity to changes in the KOSPI index.A beta coefficient close to zero indicates that this stock has low sensitivity to changes in the index or factors measured in this model.The high statistical significance value of 0.868 suggests that the relationship is not statistically significant.

Hypothesis Testing
H 1 : there is a significant difference in abnormal returns before and after Park Ji Min's solo debut H 2 : there is a substantial difference in stock prices before and after Park Ji Min's solo debut H 3 : there is a significant difference in beta risk before and after Park Ji Min's solo debut.In addition, there is a null hypothesis (H0), which states no significant difference in each variable.
Hypothesis testing will be carried out through the Paired Sample T-Test test, Wilcoxon Signed Rank Test, and Single Index Model Regression Technique.The Paired Sample T-Test test will be used if the data is proven to be normally distributed, provided that the sig.A value smaller than 0.05 means the proposed hypothesis is accepted, and the null hypothesis is rejected.The Wilcoxon Signed Rank Test will be used if the data is proven abnormally distributed, provided that the Asymp.Sig.(2 tailed) more petite than 0.05 means the proposed hypothesis is accepted, and the null hypothesis is rejected.The Single Index Model Regression technique will be used on the beta risk variable, as seen from the coefficient-beta value generated in each period.The for the proposed hypothesis to be accepted is if there is a difference in the coefficient.Beta value in each period.If beta = 1, the asset tends to align with the market.If the beta is greater than 1, the asset is more volatile than the market, while if the beta is smaller than 1, the asset is less volatile than the market.The null hypothesis will be accepted if the resulting coef.Beta values in both periods are equal to one, more than one, or less than one.

Abnormal Return and Park Ji Min's Solo Debut
The study's findings reveal insufficient evidence to support the hypothesis (H1) that there is a significant difference in abnormal returns before and after Park Ji Min's solo debut.Contrary to the expectations grounded in signaling theory, which suggests that substantial events should lead to observable changes in market behavior, the results indicate no significant variation of abnormal returns during the periods surrounding the debut.This suggests that either the market anticipated the debut, resulting in a lack of reaction, or the event needed to be more impactful to influence investor behavior significantly.The rejection of H1 and acceptance of the null hypothesis (H0) indicates that Park Ji Min's solo debut did not lead to a significant difference in abnormal returns, challenging the assumption that such events should trigger noticeable market responses.This finding aligns with studies byBahri & Fatchurrohman (2023), Hotimah & Astawinetu (2020), Santoso &Silitonga (2023), andSoraya (2023), which also found that certain events or announcements do not always lead to significant changes in abnormal returns.These studies support the idea that markets may only sometimes react strongly to specific events, particularly when those events are anticipated or perceived as less impactful.
However, the results contrast with the findings of Cung & Rakhmat (2022), Chofifah & Suryani (2022), Lubis et al. (2023), andMachfudi &Isynuwardhana (2023), who reported significant changes in abnormal returns following major entertainment industry events, such as artist debuts.This discrepancy could be due to differences in the events studied, market conditions, or methodologies.The market's reaction to Park Ji Min's solo debut was muted compared to other events analyzed in these previous studies.These findings have practical implications for investors and market analysts, highlighting the need for caution when assessing the impact of celebrity-driven events on stock prices.The results suggest that not all such events significantly affect market performance, emphasizing the importance of considering a broader range of factors when evaluating potential market impacts.For companies like HYBE Corporation, this outcome indicates that entertainmentrelated milestones may not always be perceived as critical drivers of stock performance, underscoring the importance of developing diversified strategies to manage investor expectations and ensure stock stability.

Stock Prices and Park Ji Min's Solo Debut
The study examined stock prices and proposed the hypothesis (H2) that "there is a significant difference in stock prices before and after Park Ji Min's solo debut."The findings confirmed this hypothesis, as H0 was rejected and H2 was accepted, a significant difference in stock prices before and after the debut.The low significance value suggests that these results reflect a genuine difference in the population, making it unlikely that the observed changes occurred by chance.These findings align with the fundamental concept that significant events, such as a highprofile artist's solo debut, can impact investor behavior and stock prices.The results support signaling theory, which posits market participants react to new, impactful information.In this case, Park Ji Min's solo debut was perceived as a significant event, influencing investor sentiment and leading to noticeable changes in stock prices.This study's results are consistent with previous research by Lubis et al. (2023), Cung &Rakhmat (2022), andWicaksono (2022), all of which found significant differences in stock prices before and after specific events.These studies highlight the role of substantial events as catalysts for stock price movements, emphasizing the importance of monitoring such occurrences for potential market impacts.However, the findings contrast with those of Pardiansyah et al. (2023), who found no significant difference in stock prices following similar events.This divergence could be due to differences in the events studied, market conditions, or methodologies.These findings suggest that investors and financial analysts should closely monitor significant events like solo debuts by prominent artists, as they can substantially impact stock prices.For companies like HYBE Corporation, understanding potential market reactions to such events can guide strategies for managing investor expectations and leveraging favorable market conditions.These insights underscore the value of incorporating event-driven analysis into investment strategies to effectively anticipate and respond to market changes.

Beta Risk and Park Ji Min's Solo Debut
The study examined beta risk, measuring the sensitivity of HYBE Corporation's stock to changes in the KOSPI index before and after Park Ji Min's solo debut.The findings revealed a significant decrease in this sensitivity following the debut.Before the debut, there was a positive relationship between HYBE's stock and the KOSPI index, indicating that HYBE's stock price moved in line with broader market trends.After the debut, however, this relationship weakened considerably, showing little to no correlation between HYBE's stock movements and the KOSPI index.The regression analysis demonstrated that, before the solo debut, HYBE Corporation's stock was sensitive to changes in the KOSPI index, closely tracking overall market fluctuations.Post-debut, the stock became less sensitive to these market changes, suggesting a shift in its risk profile.These results support the hypothesis (H3) that there is a significant difference in beta risk before and after Park Ji Min's solo debut, leading to the rejection of the null hypothesis (H0).
This shift in beta risk indicates that Park Ji Min's solo debut considerably impacted HYBE's stock behavior amid market volatility, signaling a change in the company's exposure to market risk.This outcome is consistent with theories suggesting that significant events can alter a stock's sensitivity to broader market movements, reflecting changes in investor perceptions and market conditions.Comparing these findings with previous research, they align with studies showing that significant events can influence a company's beta risk.However, the observed decrease in beta risk after the debut contrasts with cases where similar events increased market sensitivity, emphasizing the unique market reaction to Park Ji Min's solo debut.These findings suggest that investors and analysts should consider how significant events, such as high-profile debuts, can alter a company's risk profile.HYBE broader market volatility, influencing investment strategies and risk management practices.These insights highlight the importance of continuously monitoring beta risk in response to significant corporate events to understand and manage the associated risks better.

Conclusion
This study investigated the impact of Park Ji Min's solo debut on HYBE Corporation's stock, focusing on abnormal returns, stock prices, and beta risk.The findings revealed no significant difference in abnormal returns before and after the debut, suggesting that the market did not react as strongly as anticipated.Conversely, the study found a substantial change in stock prices, reflecting a positive market evaluation of Park Ji Min's debut.Additionally, a notable shift in beta risk indicated that HYBE's stock became less sensitive to broader market movements after the debut.
The value of this research lies in its contribution to understanding how major entertainment events, such as a high-profile solo debut, can influence stock performance and risk profiles.This study is original in its focus on Park Ji Min's debut and its detailed examination of beta risk alongside traditional stock performance metrics.The findings have practical and managerial implications, suggesting that companies like HYBE Corporation should know how such events can alter investor perceptions and market dynamics.The results highlight the importance of considering event-driven risk when making investment decisions for investors.
However, this study has limitations.The focus on a single company, HYBE Corporation, limits the generalizability of the findings.Future research should expand the scope to include other major companies in the South Korean entertainment industry, particularly those within the Big Four, to assess the broader impact of solo debuts by internationally famous groups like BTS.Employing different analytical tools could provide further insights into market reactions and stock performance.Future researchers are encouraged to explore these avenues to build on the foundation laid by this study.

Figure 1 .
Figure 1.HYBE Corporation Stock Price Chart Since IPO Until the End of 2021

Figure 2 .
Figure 2. HYBE Corporation Stock Price Chart After BTS Hiatus Announcement Source: finance.yahoo

Figure 3 .
Figure 3. Dior Stock Price Chart After Park Ji Min Became Global Brand Ambassador Source: investing.com

H 2 :
There is a Change in Stock Price Before and After Park Ji Min's Solo Debut Beta Risk Changes Before and After Park Ji Min's Solo Debut

Advances in Applied Accounting Research, 2(3), 2024. 169 -183 DOI: https://doi.org/10.60079/aaar.v2i3.145 where
in the study "Differential Analysis of the Rate of Return and Beta Risk of Shares Before and During the COVID-19 Case in Consumer Goods Companies on the IDX for the 2018-2021 Period" by Kennedy et al. (

Table 1 .
Descriptive Statistical Analysis Test of HYBE Corporation's Abnormal Return Before and After Park Ji

Table 2 .
Test of Descriptive Statistical Analysis of HYBE Corporation's Stock Price Before and After Park Ji Min's Solo Debut (Descriptive Statistics)

Table 3 .
Normality Test of Abnormal Return of HYBE Corporation Before and After the Solo Debut of Park Ji MinThe test results table for abnormal return data for both periods, before and after Park Ji Min's solo debut, shows that the significance value (Sig.) for each period is 0.200, and the test statistic value for each group is 0.111. is 0.125, and the degree of freedom (df) is 30.These results indicate Source: SPSS 29 output results (data processed)

Advances in Applied Accounting Research, 2(3), 2024. 169 -183 DOI: https://doi.org/10.60079/aaar.v2i3.145 that
statistically, there is insufficient evidence to reject the hypothesis that the two data sets are typically distributed.In other words, this result means that H0 is accepted or can be interpreted as the data being usually distributed.

Table 4 .
Normality Test of HYBE Corporation Stock Price Before and After Park Ji Min's Solo Debut (Tests of Normality)

Table 5 .
Paired Sample T-Test of Abnormal Return of HYBE Corporation Before and After the Solo Debut of Park Ji Min

Table 6 .
Wilcoxon Signed Rank Test of HYBE Corporation Stock Price Before and After Park Ji Min's Solo Debut HYBE Corporation Stock Price After Park Ji Min's Solo Debut < Stock Price Before Park Ji Min's Solo Debut b.HYBE Corporation Stock Price After Park Ji Min's Solo Debut > Stock Price Before Park Ji Min's Solo Debut c. HYBE Corporation Stock Price After Park Ji Min's Solo Debut = Stock Price of HYBE Corp.Before Park Ji Min's Solo Debut Source: SPSS 29 output results (data processed)

Table 7 .
Wilcoxon Signed Rank Test of HYBE Corporation Stock Price Before and After the Solo Debut of Park Ji Min 2 (Test Statistics a )

Table 8 .
Regression Technique Test of Single Index Model Risk Beta Shares of HYBE Corporation Before Park Ji Min's Solo Debut (Coefficients a )

Table 9 .
Regression Technique Test of Single Index Model Risk Beta Shares of HYBE Corporation After the Solo Debut of Park Ji Min (Coefficients a )