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\line{Paul Coddington,\hfill}
\line{Physics Department,\hfill}
\line{Syracuse University,\hfill}
\line{Syracuse, NY 13244.\hfill}
\bigskip
\line{Tel: (315) 443-1573\hfill}
\line{FAX: (315) 443-9103\hfill}
\line{Email: paulc@sccs.syr.edu\hfill}
\bigskip
\line{12/10/91\hfill}
\bigskip
\line{Your ref: LJ4607\hfill}
\bigskip
\bigskip
\noindent
Dear Sir,
\bigskip

This in reply to your FAX of December 6, concerning the paper
``Empirical relations between static and dynamic exponents for 
Ising model cluster algorithms''
by Paul D. Coddington and Clive F. Baillie, 
which was rejected for publication by Physical Review Letters.

Referee A criticized the paper for not defining many of the terms
used in the paper. We believe this is a reasonable criticism, and
have made a number of changes to the manuscript to overcome this
problem. 

On page 3 we have added definitions of the autocorrelation time
$\tau$ and the dynamical critical exponent $z$. On page 4 we have
defined the critical exponents $\gamma$ and $\nu$,
and on page 5 the exponent $\alpha$. We have also
clarified our definition of the magnetization exponent $\beta$ on
page 6. 

The only remaining objection of referee A (referee B found the paper
acceptable for publication) was that the algorithms
themselves have not been defined. However we believe that this is
unwarranted in the case of a short letter, mainly on the grounds
that it will take up a lot of space, which will mean that some of 
the results will have to be omitted in order for the paper to meet
the length requirements. Also, we believe that anyone who would
be even remotely interested in reading this paper would be familiar
enough with the cluster algorithms that rehashing their definitions
would be unneccessary. Even if readers are not familiar with the 
algorithms, the details of the algorithms are not crucial to the
understanding of the results presented, and if people read the paper 
and find that they want to know more about it, it is a simple matter 
to find one of the review articles or original references which are 
cited in our paper.

Recent articles concerning cluster algorithms which 
have been published in Phys. Rev. Lett. and other journals have merely
referenced the Swendsen-Wang and Wolff algorithms, and not described
them in any way, e.g. 
D. Kandel et al., Phys. Rev. Lett. {\bf 65}, 941 (1990); 
J.-S. Wang, Physica A {\bf 164}, 240 (1990).


We would therefore like to resubmit our paper to Physical Review
Letters.

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Yours sincerely,

\vfill
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