| 執筆者 | 福川 信也（東北大学） |
|---|---|
| 発行日/NO. | 2023年8月 23-E-062 |
| 研究プロジェクト | 国際的に見た日本産業のイノベーション能力の検証 |
| ダウンロード/関連リンク |
概要
公設試験研究機関(公設試)の法人化は自治体の判断に委ねられており、法人化のタイミングも自治体によって異なる。実施のタイミングの異なる政策の評価において標準的な差の差モデルにより推定された治療効果はバイアスを受ける可能性がある。本研究は公設試法人化の効果を標準的な差の差モデルとバイアス補正差の差モデルで推計した。分析結果によれば、知識創造に関する変数については両者とも治療効果は有意に正であるが、知識普及に関する変数については補正モデルの結果は非有意である。具体的には、晩期に法人化された公設試ほど技術相談を縮小し、学位取得者と特許出願を強化した。本研究は公設試法人化の効果の異質性が生じる背景を集積の外部性、産業の知識ベース、組織学習能力の観点から考察する。
概要（英語）
A series of public administration reforms were implemented in Japan to cope with the secular stagnation since the 1990s, some of which took the form of the incorporation of public organizations. Drawing on the incorporation of Kohsetsushi, technology extension service providers established by local governments, which was a policy program implemented in the early 2000s, this study evaluates its average treatment effect on the treated (ATT) by applying the difference-in-differences (DID) model to panel data (2000-2021). Unlike the uniform and simultaneous incorporation of national universities, it was local governments that decided whether and when to incorporate their Kohsetsushi, which implies a staggered treatment. Applying the conventional two-way fixed effects DID (TWFE DID) model to panel data with staggered treatments may yield biased ATTs due to forbidden comparisons between late and early treated units where early treated units are used as a control group. This study adopted the DID model proposed by Callaway and Sant’Anna (2021) (CS DID) to correct the bias by avoiding contaminated comparisons. The ATTs in terms of scientific knowledge and inventive activities are significantly positive for both models. In contrast, the ATTs in terms of technology extension are heterogeneous and significantly positive for the TWFE DID model but insignificant for the CS DID model. Sources of heterogeneity are discussed from the perspectives of agglomeration externalities, learning capacity, and industrial knowledge bases.
