Among the recently accepted research papers by the top$-$tier conferences or journals in the field of Information Retrieval, identify the trends of research topics and methods. In your report, describe the trends and explain the reasons behind them. Select a few papers on a common research topic that you find intriguing and describe the research problems, methods, and results presented in the papers. You must cite the papers properly. You can use the figures from the original papers to help you illustrate the research problems and methods.