When Victims Happen to Be Black

When bad things happen to good trees

When the edges in a tree or rooted tree fail with a certain fixed probability, the (greedoid) rank may drop. We compute the expected rank as a polynomial in p and as a real number under the assumption of uniform distribution. We obtain several different expressions for this expected rank polynomial for both trees and rooted trees, one of which is especially simple in each case. We also prove tw...

When Bad Things Happen to Good Campuses

G ene Washington, director of acdemic computing, is buzzed by his secretary to take an urgent call from Provost Marion Mossback. “Washington,” yells Mossback, “what kind of trouble have you got Ypsilanti University into now?” After a few minutes of gentle probing, Washington has the outline of the “trouble.” Mossback has just received a letter from a prominent alumnus and benefactor, Mr. Martin...

When does grouping happen?

Recent research on perceptual grouping is described with particular emphasis on identifying the level(s) at which grouping factors operate. Contrary to the classical view of grouping as an early, two-dimensional, image-based process, recent experimental results show that it is strongly influenced by phenomena related to perceptual constancy, such as binocular depth perception, lightness constan...

When VAD Things Happen to Good People.

When does grouping happen ? q

Recent research on perceptual grouping is described with particular emphasis on identifying the level(s) at which grouping factors operate. Contrary to the classical view of grouping as an early, two-dimensional, image-based process, recent experimental results show that it is strongly influenced by phenomena related to perceptual constancy, such as binocular depth perception, lightness constan...