### Educational Background

- Ph.D. in Mathematics, University of Michigan
- M.S. in Operations Research, Case Western Reserve University
- B.A. in Mathematics, Carleton College

### Research Interests

- Hilbert space operator theory
- Weak subnormalities
- Mathematical cognition

### Selected Publications

Some new elements in the class 𝔸ℵ₀ J. Operator Theory, 16 (1986), 203-212.

Sur la réflexivé des contractions sur l'espace hilbertien (with B. Chevreau, C. Pearcy) C.R. Acad.Sci. Paris, t.305, Serie I, (1987), 117-120.

*C.*₀ contractions: dual operator algebras, Jordan Models, and multiplicity (with Y. Jo, I. Jung)

J. Operator Theory, 33 (1995), 381-394.

Boundary sets for a contraction (with B. Chevreau, C. Pearcy) J. Operator Theory, 34 (1995), 347-380.

Weakly *n*-hyponormal weighted shifts and their examples (with I. Jung and S. Park) Integral Equations Operator Theory 54, (2006), 215-233.

Aluthge transforms and n-contractivity of weighted shifts Journal of Operator Theory, 61:2(2009), 419-438.

*k*-hyponormality and n-contractivity for Agler-type shifts (with G. Adams) Journal of Operator Theory, in press.

Backward extensions of recursively generated weighted shifts and quadratic hyponormality (with I. Jung, M. Lee, S. Park) Integral Equations Operator Theory, in press.