[1][3] She was a faculty member in the mathematics department of Towson University from 1971 until 2015, when she became a professor emerita.
[1] Siegel grew up in Brooklyn, the daughter of civil engineer Nat Jochnowitz.
[3] She did her undergraduate studies in mathematics at Russell Sage College, a small women's college in Troy, New York, while also taking classes at the nearby men-only Rensselaer Polytechnic Institute,[4] as at that time Russell Sage had no mathematics department.
[5] She completed her Ph.D. in 1969 at the University of Rochester; her dissertation, On Birth and Death Processes, was supervised by Johannes Kemperman.
[4] At Towson, in 1981, Siegel founded an innovative and still-ongoing undergraduate applied mathematics program involving projects connected to local business and government.