The Statistics Department hosts weekly colloquia on a variety of statistcal subjects, bringing in speakers from around the world.
Type of Event:
Many robust tests have been proposed in the literature to compare two hazard rate functions, however, very few of them can be used in cases when there are multiple hazard rate functions to be compared. In this paper, we propose an approach for detecting the difference among multiple hazard rate functions. Through a simulation study and a real-data application, we show that the new method is robust and powerful in many situations, compared with some commonly used tests.
Micro-randomized trials are trials in which individuals are randomized 100's or 1000's of times over the course of the study. The goal of these trials is to assess the impact of momentary interventions, e.g. interventions that are intended to impact behavior over small time intervals. A fast growing area of mHealth concerns the use of mobile devices for both collecting real-time data, for processing this data and for providing momentary interventions. We discuss the design and analysis of these types of trials.
Irreproducible biomedical research is particularly concerning because flawed findings have the potential to make their way to clinical studies involving human participants. Many factors have been suggested as contributors to irreproducibility, including poor study design, analytic instability of measurement methods, sloppy data handling, inappropriate and misleading statistical analysis methods, improper reporting or interpretation of results, and on rare occasions, outright scientific misconduct.
The purpose of the 2014 SAS Data Analytics Shootout problem was to study the effect of various seasonal, economic, demographic, and climatological conditions on crime rates in five large US cities (Atlanta, Chicago, Denver, Houston, and Sacramento). Hourly precinct-level crime records for seven different crime types were provided for each city for different time periods between 2005 and 2012. Demographic and social economic data for each city were also provided, based on census data.
A vast majority of the published cancer studies in the past few decades was conducted on cancer cells rather than cancer tissues. Knowing that the microenvironment plays key roles in cancer initiation, development and metastasis, we must reassess the true relevance of many of these published results to cancer. We have recently developed a new framework for cancer studies by treating cancer as a survival process under increasingly more challenging stresses, which evolve as a cancer evolves.
In this talk the three-factor Fama-French regression model (1992~1995) is introduced, where the three factors are the market risk premium (MRP), small-minus-big risk premium (SMB) and high-minus-low risk premium (HML). It is known that the factors MRP, SMB and HML can affect a stock portfolio’s return. According to the Fama-French regression model, their six types of stock portfolios created by company size (Small or Big) and its ratio of book-to-market equity (High, Medium or Low) can explain 90+% of the return for a portfolio.