**5. Conclusion**

In order to reveal how the factors influence the shrinking cities in Northeast China from the perspective of equality, this paper established the URD model to measure the urban resource degree. Given the spillover effect and heterogeneity of the influencing factors, SDM and GTWR were used to conduct an empirical analysis of the URD of shrinking cities. The findings are summarized as follows:


From that above results, we proposed the policy implications from the perspectives of (1) strengthening competitive industries and implementing urban transformation and upgrading, (2) strengthening system design and optimizing regional urban arrangement, and (3) increasing investment in science and technology, and enhancing the innovation capabilities. URD indicates the resource endowment and the ability to compete with external resources of the shrinking cities. Therefore, it is indispensable to create reasonable planning and layout within the region in order to avoid disorderly development resulting from the negative spillover effect and make full use of the positive spillover effects of these factors to achieve the comprehensive effect of "1 + 1 > 2". We hope the findings can provide supports for related policy-making.

**Author Contributions:** Conceptualization, Y.W., J.G. and M.L.; methodology, Y.W. and J.G.; software, Y.W.; validation, Z.Z. and M.L.; formal analysis, Y.W. and M.L.; investigation, J.G.; resources, Y.W.; writing—original draft preparation, Y.W. and J.G.; writing—review and editing, J.G.; supervision, J.G. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research has no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** This research has been supported by the Science and Technology Research Program of Chongqing Municipal Education Commission (KJQN201801533, KJQN201801534).

**Conflicts of Interest:** The authors declare no conflict of interest.
