As a representative emerging machine learning technique, federated learning(FL) has gained considerable popularity for its special feature of “making data available but not visible”. However, potential problems rema...As a representative emerging machine learning technique, federated learning(FL) has gained considerable popularity for its special feature of “making data available but not visible”. However, potential problems remain, including privacy breaches, imbalances in payment, and inequitable distribution.These shortcomings let devices reluctantly contribute relevant data to, or even refuse to participate in FL. Therefore, in the application of FL, an important but also challenging issue is to motivate as many participants as possible to provide high-quality data to FL. In this paper, we propose an incentive mechanism for FL based on the continuous zero-determinant(CZD) strategies from the perspective of game theory. We first model the interaction between the server and the devices during the FL process as a continuous iterative game. We then apply the CZD strategies for two players and then multiple players to optimize the social welfare of FL, for which we prove that the server can keep social welfare at a high and stable level. Subsequently, we design an incentive mechanism based on the CZD strategies to attract devices to contribute all of their high-accuracy data to FL.Finally, we perform simulations to demonstrate that our proposed CZD-based incentive mechanism can indeed generate high and stable social welfare in FL.展开更多
EFL （English as a Foreign Language） speaking is a very demanding skill that requires learners＇ socio-pragmatic as well as strategic competence in any interactional situation, and lexis proves to play a crucial role...EFL （English as a Foreign Language） speaking is a very demanding skill that requires learners＇ socio-pragmatic as well as strategic competence in any interactional situation, and lexis proves to play a crucial role in this process. However, few studies have investigated how both EFL teachers and learners view and analyze situations in which learners are not producing enough spoken language in class, and the reasons behind them. The present study will pinpoint the significant role of lexis in Moroccan learners＇ speaking production. To this end, 40 EFL teachers and 200 Moroccan high school students are surveyed and interviewed to reveal their perceptions of the speaking skill and the corresponding high significance of lexis in this instance. Results show that both teachers and learners identify vocabulary deficiency as the main factor behind students＇ inability to speak English. In the present paper, among the many suggestions that could be proposed to deal with this situation, it is argued that one efficient way would be to assist the students during the process of L2 （second language） vocabulary learning through vocabulary learning strategy instruction. Pedagogical and research implication will be given in response to the difficulties encountered in this area as have been identified by the EFL teachers and learners surveyed.展开更多
基金partially supported by the National Natural Science Foundation of China (62173308)the Natural Science Foundation of Zhejiang Province of China (LR20F030001)the Jinhua Science and Technology Project (2022-1-042)。
文摘As a representative emerging machine learning technique, federated learning(FL) has gained considerable popularity for its special feature of “making data available but not visible”. However, potential problems remain, including privacy breaches, imbalances in payment, and inequitable distribution.These shortcomings let devices reluctantly contribute relevant data to, or even refuse to participate in FL. Therefore, in the application of FL, an important but also challenging issue is to motivate as many participants as possible to provide high-quality data to FL. In this paper, we propose an incentive mechanism for FL based on the continuous zero-determinant(CZD) strategies from the perspective of game theory. We first model the interaction between the server and the devices during the FL process as a continuous iterative game. We then apply the CZD strategies for two players and then multiple players to optimize the social welfare of FL, for which we prove that the server can keep social welfare at a high and stable level. Subsequently, we design an incentive mechanism based on the CZD strategies to attract devices to contribute all of their high-accuracy data to FL.Finally, we perform simulations to demonstrate that our proposed CZD-based incentive mechanism can indeed generate high and stable social welfare in FL.
文摘EFL （English as a Foreign Language） speaking is a very demanding skill that requires learners＇ socio-pragmatic as well as strategic competence in any interactional situation, and lexis proves to play a crucial role in this process. However, few studies have investigated how both EFL teachers and learners view and analyze situations in which learners are not producing enough spoken language in class, and the reasons behind them. The present study will pinpoint the significant role of lexis in Moroccan learners＇ speaking production. To this end, 40 EFL teachers and 200 Moroccan high school students are surveyed and interviewed to reveal their perceptions of the speaking skill and the corresponding high significance of lexis in this instance. Results show that both teachers and learners identify vocabulary deficiency as the main factor behind students＇ inability to speak English. In the present paper, among the many suggestions that could be proposed to deal with this situation, it is argued that one efficient way would be to assist the students during the process of L2 （second language） vocabulary learning through vocabulary learning strategy instruction. Pedagogical and research implication will be given in response to the difficulties encountered in this area as have been identified by the EFL teachers and learners surveyed.
