Retrieval-Update Speed Tradeoffs Using Combined Indices
In a paper in the November 1970 Communications
of the ACM, V. Y. Lum introduced a technique 
of file indexing named combined indices.  This technique
permitted decreased retrieval time at the cost 
of increased storage space.  This paper examines combined
indices under conditions of file usage with 
different fractions of retrieval and update.  Tradeoff
curves are developed to show minimal cost of file 
usage by grouping various partially combined indices.
CACM December, 1971
Mullin, J. K.
