Developing robust and refined measures to quantify strategic impacts is a major challenge facing researchers who seek to
improve methods for information technology (IT) investment evaluation. This paper presents a means to test for parameter
heterogeneity in a model which quantifies the strategic contribution of IT. An iterative "jackknife" procedure is used to
diagnose if different local competitive and demographic conditions present in branch banking enhance or suppress leverage
on deposit market share associated with membership in an automated teller machine (ATM) network. The results are
validated using correlation analysis and re-estimating partitioned data sets for a market share model developed by Banker and
Kauffman (1988). Overall, the results suggest this new approach will be useful for managers who need to evaluate similar ITS
which operate in different environments.Information Systems Working Papers Serie