一間企業花了大筆鈔票，只為了買下一支球隊之球衣上直徑不到五公分的角落， 擺上自家公司的商標，整個投資的效益是否有反應在股價上?本研究搜集了 NBA 球衣廣告合約 2017 年至 2020 年期間三十支球隊中贊助商為上市公司的十四支球 隊的每場比賽資訊，探討球隊勝負及賽後網路聲量對於其贊助商股票異常報酬率 的影響，其中網路聲量的計算方式為透過網路爬蟲抓取比賽後網路相關新聞，將 新聞內文經過情感分析後，得出一個足以判斷其為正面或負面新聞的情感分數， 作為一個體現球隊表現的變數。應變數方面為球隊贊助商之異常報酬，為日報酬 率減去以大盤指數計算得出的預期報酬的結果。本研究以事件研究法將比賽日設 為事件日，以 OLS 迴歸模型，計算出事件其發生前後是否有顯著差異。結果顯示 球隊比賽吞敗對於贊助商異常報酬有顯著負相關，且此效果大部分來自戰績好的 球隊；比賽勝利則無顯著影響。網路聲量方面的結果顯示，戰績差的球隊因輸球 有助於球隊在選秀大會上取得前面的順位，對於投資者來說反而是好消息，導致 了新聞聲量與球隊贊助商異常報酬顯著負相關的結果；戰績好的球隊則是可以從 季後賽樣本得出新聞聲量與贊助商異常報酬顯著正相關的結果。

Company spends a lot of money to purchase a space of a sport team's jersey and puts its own company's trademark symbol on it. Is it worthwhile when the company’s symbol is less visible when the ad patch is less than five centimeters in diameter? The purpose of this study is to investigate whether the performance of games and the online voice after the games will affect the stock performance of the team’s sponsors. In particular, among the 30 NBA teams having NBA jersey advertising contracts from 2017 to 2020, there are 14 NBA teams whose sponsors are exchange-listed companies. This study collects information on each game of these 14 NBA teams over the period from 2017 to 2020. Web crawlers are used to capture relevant Internet news after the game and the volume of Internet voice is calculated. Furthermore, a sentiment score is calculated when sentiment analysis is applied to the news content, in which a sentiment score represents whether the net volume of news is positive or negative based on sufficient information. This study uses the event study method, setting the match day as the event day, and using the OLS regression model to calculate whether there is a significant difference before and after the event. The dependent variable is the abnormal return of the team sponsor, in which daily rate of return minus the expected return derive from the market model is used to proxy abnormal return. The results show that team defeats had a significant negative correlation with the abnormal return of sponsors, and this effect mostly comes from teams with good records; victory in the game didn’t have such significant effect. The results of the online volume show that a team with a rather bad record will help the team to get the top pick in the draft due to the loss. This is good news for investors, resulting that the news volume and abnormal return of team sponsors are significantly negatively correlated. Finally, from the playoff-season sample, the teams with a good record show that the volume of news is significantly positively correlated with the abnormal return of the sponsors.

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資料庫及其他資料來源:
Sports Reference: https://www.sports-reference.com/
NLTK: https://www.nltk.org/book/
ESPN: https://www.espn.com/
Sports Illustrated: https://www.si.com/
Bleacher Report: https://bleacherreport.com/