Trafficking in persons is a crime that poses exceptional challenges when it comes to measurement. For this reason, the literature on trafficking has only recently developed a set mass of quantitative estimates, although this remains insufficient to conduct studies at an international level. This lack of data has limited the possibility for quantitative studies and in particular the development of statistical models. Statistical models are extensively used in other social sciences to identify determinants that may increase or reduce the severity of a social phenomenon. This paper suggests the use of official administrative statistics on detected victims of trafficking in persons to develop quantitative models on human trafficking flows. The methodological approach suggested in this paper allows for identifying the factors explaining why certain countries—and not others—are relevant origins of trafficking flows into selected destination countries. These factors are found to be geographical distance to selected destinations, population size and level of organised crime. This result is in line with the few other quantitative studies on the determinants of trafficking, mainly framed in static gravity models. In addition, this paper proposes a dynamic approach to the determinants of trafficking flows. Trafficking flows change over time, and the relevance of certain places of origin may increase or decrease according to certain factors. This study flags variations in unemployment and national wealth in countries of origin as two factors affecting outflows of human trafficking.

贩运人口是一种犯罪，在衡量方面提出了特殊的挑战。出于这个原因，关于贩运的文献直到最近才发展出大量的定量估计，尽管这仍然不足以在国际层面进行研究。缺乏数据限制了定量研究的可能性，特别是统计模型的发展。统计模型在其他社会科学中被广泛使用，以识别可能增加或减少社会现象严重性的决定因素。本文建议使用有关已发现人口贩运受害者的官方行政统计数据来开发人口贩运流动的定量模型。本文建议的方法允许确定解释为什么某些国家（而不是其他国家）是贩运流入选定目的地国的相关来源的因素。发现这些因素是与选定目的地的地理距离、人口规模和有组织犯罪的程度。这一结果与其他少数关于贩运决定因素的定量研究一致，主要以静态重力模型为框架。此外，本文提出了一种动态方法来确定贩运流动的决定因素。贩运流量随时间而变化，某些来源地的相关性可能会根据某些因素而增加或减少。这项研究将原籍国的失业率和国民财富的变化列为影响人口贩运流出的两个因素。