Speaker: Fan Dai, Michigan Technological University 

Time: Wednesday, January 17, 2:30pm-3:30pm 

Place: Virtual 

Zoom link:  

https://wayne-edu.zoom.us/j/96316494795?pwd=Ylc3M0R0R1BYaUZGSnB2dkI2UFRVQT09 

Title: Exploratory Factor Analysis of Data on a Sphere 

Abstract: Data on high-dimensional unit spheres arise frequently in many disciplines either naturally or as a consequence of preliminary processing and can have complex dependence structures that need to be understood. We develop exploratory factor analysis of the projected normal distribution to explain the variability in such data using a few easily interpreted latent factors. Our methodology provides maximum likelihood estimates through a fast novel alternating expectation profile conditional maximization algorithm, and gives interpretable and insightful results when applied to tweets with the #MeToo hashtag from early December 2018, to time-course functional Magnetic Resonance Images of the average pre-teen brain at rest, to characterize handwritten digits, and to gene expression data from cancerous cells in the Cancer Genome Atlas.