In this study, we used company level administrative data from the National Labour Inspectorate and The Polish Social Insurance Institution in order to estimate the prevalence of informal employment in Poland in 2016. Since the selection mechanism is non-ignorable, we employed a generalization of Heckman’s sample selection model assuming non-Gaussian correlation of errors and clustering by incorporation of random effects. We found that 5.7% (4.6%, 7.1%; 95% CI ) of registered enterprises in Poland, to some extent, take advantage of the informal labour force. Our study exemplifies a new approach to measuring informal employment, which can be implemented in other countries. It also contributes to the existing literature by providing, to the best of our knowledge, the first estimates of informal employment at the level of companies based solely on administrative data.

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基于不可忽略选择机制的行政记录估计非正规就业规模

在本研究中，我们使用来自国家劳动监察局和波兰社会保险机构的公司级行政数据来估计 2016 年波兰非正规就业的普遍程度。由于选择机制是不可忽略的，我们采用了 Heckman 的概括样本选择模型假设误差的非高斯相关性和通过结合随机效应进行聚类。我们发现，5.7% (4.6%, 7.1%; 95% CI ) 的波兰注册企业在一定程度上利用了非正规劳动力。我们的研究举例说明了衡量非正规就业的新方法，该方法可以在其他国家实施。据我们所知，它还通过提供现有文献，