The increase in carbon emissions is considered one of the major causes of global warming and climate change. To reduce the potential environmental and economic threat from such greenhouse gas emissions, governments must formulate policies related to carbon emissions. Most economists favor the carbon tax as an approach to reduce greenhouse gas emissions. This market-based approach is expected to inevitably affect enterprises’ operating activities such as production, inventory, and equipment investment. Therefore, in this study, we investigate a production inventory model for deteriorating items under a carbon tax policy and collaborative preservation technology investment from the perspective of supply chain integration. Our main purpose is to determine the optimal production, delivery, ordering, and investment policies for the buyer and vendor that maximize the joint total profit per unit time in consideration of the carbon tax policy. We present several numerical examples to demonstrate the solution procedures, and we conduct sensitivity analyses of the optimal solutions with respect to major parameters for identifying several managerial implications that provide a useful decision tool for the relevant managers. We hope that the study results assist government organizations in selecting a more appropriate carbon emissions policy for the carbon reduction trend.

Prospect theory can predict the January effect. The capital gains overhang is a dominant variable in predicting the January effect, and past returns are only a noisy proxy. Empirical results based on date from Taiwan support our argument. At the beginning of every January, as proposed by the prospect theory, stocks with the lowest capital gains overhang induce investors to hold on to their losing stocks, which in turn restricts available supply and reduces selling pressure in January. Thus, because investors are willing to sell only at a premium, trading takes place at an inflated price, which causes the January effect.

This study examines whether and how the interaction between extreme market movements and the disposition effect can affect subsequent return spreads between stocks with large paper losses and those with large paper gains for a sustained period of time. We study all the A-shares listed on the Shanghai Stock Exchange and the Shenzhen Stock Exchange. Based on the prospect theory, our results show that after extreme negative market movements, the disposition effect enhances significant subsequent return spreads; however, it generates insignificant subsequent return spreads when extreme market movements are positive.