Internal and External R&D: A Sample Selection Approach*
强调企业是否进行外部研发取决于其是否先决定进行内部研发，因此需要采用纠正样本选择偏差的联合分析方法。基于意大利制造业企业数据，结果证实了该方法的必要性，并揭示了影响企业独立或合作研发决策的因素。
Abstract This study underlines that the decision to enter into an external R&D relationship is related to an antecedent decision to carry out R&D. This calls for an empirical approach that permits the joint analysis of the determinants of the two decisions, correcting for sample selectivity. Based on a sample of Italian manufacturing firms, the results confirm the need to adopt this approach. Another contribution made by this study is the managerial implications that can be derived from its empirical model, which provide a better understanding of the factors associated with a firm's decision to engage in R&D both independently and with external partners.