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A threshold varying-coefficient autoregressive model for analyzing the influence of media reports of suicide on the actual suicides. (English) Zbl 1464.62487
Summary: The extensive coverage of suicides in the media has long been considered a trigger for copycat suicides. However, evidence of such an effect is indirect and, thus, inconclusive. Here, we propose a flexible threshold autoregressive model to examine whether suicides reported in the media influence actual suicides and, thus, identify a possible copycat effect. In particular, we employ a penalized smoothing least squares estimator to conveniently estimate the parameters and unknown functions of the proposed model. We evaluate the performance of the proposed method using simulation studies, and examine the asymptotic behavior of the corresponding estimators under mild regularity conditions. Lastly, we apply our model to investigate the relationship between the daily suicide incidence and the number of suicides reported in a top-selling tabloid newspaper in Hong Kong between January 2002 and December 2006. Our results identify a copycat suicide effect due to excessive media reporting, as well as the threshold number of reports that may trigger such an effect.
MSC:
62P15 Applications of statistics to psychology
62P10 Applications of statistics to biology and medical sciences; meta analysis
62P25 Applications of statistics to social sciences
62M10 Time series, auto-correlation, regression, etc. in statistics (GARCH)
62F12 Asymptotic properties of parametric estimators
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[40] Huazhen Lin
[41] Center of Statistical Research, 555 Liutai Avenue, Wenjiang District, Chengdu, Sichuan 611130,
[42] P.R. China.
[43] E-mail: linhz@swufe.edu.cn
[44] Jiakun Jiang
[45] Weiqing Building, Room 114, Tsinghua University, Beijing 100091, P.R. China.
[46] E-mail: jiakunj@mail.tsinghua.edu.cn
[47] Binhuan Wang
[48] 180 Madison Avenue, Suite 450, New York, NY 10016, USA. · JFM 22.0492.04
[49] E-mail: Binhuan.wang@nyulangone.org
[50] Paul S. F. Yip
[51] CJT-534, 5/F, The Jockey Club Tower, The Centennial Campus, HKU, HK.
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