人是群體動物，需要滿足關係歸屬感，因傳播科技的發達，使網路成為滿足孤獨感或逃避現實之媒介，可能導致過度使用網路之問題，增加網路成癮的風險。本研究使用臺灣傳播調查資料庫 (2019) 資料，以18歲以上成年人為研究對象，探討臺灣孤獨感對網路成癮行為的影響，除此之外，亦將性別與年齡做分組，藉此了解不同性別與年齡孤獨感的差異是否對網路成癮造成影響。因先前文獻證實孤獨感與網路成癮存在內生性問題，因此使用工具變數法(Instrument variable, IV) 處理其內生問題，工具變數為週低落天數與週焦慮天數，估計方法為兩階段迴歸估計法(Two-stage Least Square, TSLS)，並考慮樣本與子樣本中可能存在異質性及弱工具變數問題，將使用一般動差法(Generalized Method of Moment, GMM)與受限訊息最大概似估計法(Limited information Maximum Likelihood, LIML)一併估計加以討論。
本研究發現：(1)相比於女性，男性孤獨感較高且網路成癮風險也較高。(2)相比於OLS，兩階段迴歸估計法更能凸顯孤獨感對網路成癮之正向效果。(3)男性與年長組(55歲以上)子樣本中存在弱工具變數問題，使用受限訊息最大概似估計法估計後，男性孤獨感對網路成癮的正向效果大於兩階段回歸估計法，而年長組則無影響。(4)出乎預期的是婚姻關係，婚姻確實能夠使孤獨感減低，而網路的方便性被用來加強婚姻聯繫，促成更多的網路使用，使成癮傾向增加。

Because of a need for relationships that lead to a sense of belongingness, the Internet is used as a medium to reduce feelings of loneliness. We use the Taiwan Communication Survey (TCS) database to discuss the effects of loneliness in Taiwan on addictive internet behavior in individuals over the age of 18. To deal with the endogenous problem in determining a relationship between loneliness and internet addiction, we use days of depression and the days of anxiety per week as the instrumental variables. We use the two-stage least square (TSLS) estimator to estimate the effect. Considering the likelihood of heterogeneity and weak instrumental variables in the sample and subsamples, generalized method of moments (GMM) and limited information maximum likelihood (LIML) are also used.
We found the following: (1) Men have the higher levels of loneliness and more risk of internet addiction than women. (2) The positive effects found using the TSLS estimator were greater than those obtained using OLS. (3) The loneliness levels of older individuals (over 55 years) have no effect on internet addiction. (4) Unexpectedly, the effect of convenience which promotes more internet use causes the higher risks in married life.

中文部分
張卿卿(2020)。傳播調查資料庫 第二期第三次(2019)：媒體使用的個人功效與影響II (D00184)【原始數據】取自中央研究院人文社會科學研究中心調查研究專題中心學術調查研究資料庫。doi:10.6141/TW-SRDA-D00184-1
英文部分
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