With the rapid expansion of the RMB exchange rate’s floating range,the effects of the RMB exchange rate and global commodity price changes on China’s stock prices are likely to increase.This study uses both auto reg...With the rapid expansion of the RMB exchange rate’s floating range,the effects of the RMB exchange rate and global commodity price changes on China’s stock prices are likely to increase.This study uses both auto regressive distributed lag(ARDL)and nonlinear ARDL(NARDL)approaches to explore the symmetric and asymmetric effects of the RMB exchange rate and global commodity prices on China’s stock prices.Our findings show that without considering the critical variable of global commodity prices,there is no cointegration relationship between the RMB exchange rate and China’s stock prices,and the coefficient of the RMB exchange rate is not statistically significant.However,when we introduce global commodity prices into the NARDL model,the result shows that the RMB exchange rate has a negative effect on China’s stock prices,that there indeed exists a long-run cointegration relationship among the RMB exchange rate,global commodity prices,and stock prices in the NARDL model,and that global commodity price changes have an asymmetric effect on China’s stock prices in the long run.Specifically,China’s stock prices are more sensitive to increases than decreases in global commodity prices.Thus,increases in global commodity prices cause China’s stock prices to decline sharply.In contrast,the same magnitude of decline in global commodity prices induces a smaller increase in China’s stock prices.展开更多
In order to promote the development of foreign trade, prevent unqualified commodities from flowing out of China and poor quality commodities from import, China’s departments of commodity inspection have strengthened ...In order to promote the development of foreign trade, prevent unqualified commodities from flowing out of China and poor quality commodities from import, China’s departments of commodity inspection have strengthened their inspection, checking supervision and management of the quality of import and export commodities. According to statistics from the State展开更多
基金supported by the Fundamental Research Funds for the Central Universities(2019CDSKXYGG0042,2018CDXYGG0054,2020CDJSK01HQ01)National Social Science Funds(16CJL007).
文摘With the rapid expansion of the RMB exchange rate’s floating range,the effects of the RMB exchange rate and global commodity price changes on China’s stock prices are likely to increase.This study uses both auto regressive distributed lag(ARDL)and nonlinear ARDL(NARDL)approaches to explore the symmetric and asymmetric effects of the RMB exchange rate and global commodity prices on China’s stock prices.Our findings show that without considering the critical variable of global commodity prices,there is no cointegration relationship between the RMB exchange rate and China’s stock prices,and the coefficient of the RMB exchange rate is not statistically significant.However,when we introduce global commodity prices into the NARDL model,the result shows that the RMB exchange rate has a negative effect on China’s stock prices,that there indeed exists a long-run cointegration relationship among the RMB exchange rate,global commodity prices,and stock prices in the NARDL model,and that global commodity price changes have an asymmetric effect on China’s stock prices in the long run.Specifically,China’s stock prices are more sensitive to increases than decreases in global commodity prices.Thus,increases in global commodity prices cause China’s stock prices to decline sharply.In contrast,the same magnitude of decline in global commodity prices induces a smaller increase in China’s stock prices.
文摘In order to promote the development of foreign trade, prevent unqualified commodities from flowing out of China and poor quality commodities from import, China’s departments of commodity inspection have strengthened their inspection, checking supervision and management of the quality of import and export commodities. According to statistics from the State
文摘针对零售商品包装变形和重叠使得难以有效捕捉显著且多样化的特征信息,导致检测精度不高的问题,设计了位置可学习视觉中心(LLVC,location learnable visual center)机制,对YOLOX-s进行改进,取得了更高的检测精度。为有效应对商品包装变形和重叠现象,首先,通过轻量级多层感知机融合不同特征通道上的信息,以充分捕获全局上下文信息;接着,通过设计的LLVC增强局部特征表示能力,并利用空间信息为局部特征分配可学习的权重,提高辨别性局部特征的关注程度;最后,将交并比(IoU,intersection over union)损失函数替换为中心交并比(CIoU,centered intersection over union),并在此基础上引入功率参数α,有效降低了漏检率。实验结果表明,所提方法在零售商品识别(RPC,retail product checkout)数据集上取得91.3%的准确率,相比YOLOX-s提高了2.2%,并优于目前主流的轻量级目标检测算法;同时每秒帧率(FPS,frame per second)为97 frame/s,模型大小为9.48 MB,能够在计算资源受限的场景下,准确且实时地进行零售商品检测。
