id author title date pages extension mime words sentence flesch summary cache txt 7m01bk1495q Douglas R. Smith A Method for Estimating Entropy of Real Birational Maps with Constrained Critical Orbits 1904 .txt text/plain 156 7 56 We particularly concern ourselves with the specific family of maps $f:\overline{\R} \ imes \overline{\R} \ ightarrow \overline{\R} \ imes \overline{\R}$ defined by $f(x,y) = \left(y\ rac{x+a}{x-1},x+a-1\ ight)$, where $a \in \R$ is a parameter subject to conditions specified later. Our method is combinatorial, using invariant and critical curves for $f$ to define a partition of $\overline{\R} \ imes \overline{\R}$ that is convenient for coding orbits under $f$. We may expand these codings to hold for points without well-defined orbits. cache/7m01bk1495q.txt txt/7m01bk1495q.txt