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{\bf Matt Scobee}
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{\bf On a Conjecture Concerning Dyadic Oriented Matroids}
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A rational matrix is {\it totally dyadic} if all of its
nonzero subdeterminants are in $\{\pm 2^k\ :\ k \in {\bf Z}\}$.
An oriented matriod is {\it dyadic} if
it has a totally dyadic representation $A$.
A dyadic oriented matriod is {\it dyadic of order $k$} if
it has a totally dyadic representation $A$ with full row rank and
with the property that for each pair of adjacent bases $A_1$ and $A_2$
$$2^{-k} \le \left| { {\det(A_1)} \over {\det(A_2)}}\right|\le 2^k.$$

In this note we present a counterexample to a conjecture
on the relationship
between the order of a dyadic oriented matroid and the ratio
of agreement to disagreement in sign of its signed circuits and
cocircuits (Conjecture 5.2, Lee (1990)).

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