Economics and Usage of Digital Libraries: Byting the Bullet
Estimation Results

The results for the exponential cdf model are consistent with expectations. They suggest that higher cost/use journals are purchased by fewer libraries. For example, in 1991, the marginal journal for a $100,000 budget library has a cost/use value equal to about 0.22 and, using the parameter estimates, is held by about 30 of the 194 libraries in the sample. The marginal journal for a $200,000 budget library has a cost/use value equal to about 0.59, and is held by some 17 libraries.

Turning to the structural model results, the estimates imply that, after controlling for changes in citation rates and costs, publishers increased annual journal prices some 140% over the 1988-98 period (over the same period the Consumer Price Index increased by 37%). In addition, as a journal's citation rate improves relative to the average value in the sample, demand increases. Demand is apparently very inelastic. No firm-specific demand elasticity was more than 0.50 in absolute value. These small elasticities imply that publishers have an incentive to more than exhaust existing library serial budgets and any anticipated increases. This observation is consistent with numerous librarians' experiences and with what some publishers have privately acknowledged. [17] However, these estimates suggest that firms are not profit-maximizing, at least not in a short-term sense. One possible explanation is that, in anticipation of future growth in serials budgets, publishers preserve future sales by pricing less aggressively today. Under such circumstances, the estimated, firm-specific demand elasticities should lie somewhere between zero and one, in absolute terms. [18] Note that this story can also account for the estimated annual price increases.

Did the two publishing mergers earlier in the decade enhance the participating firms' market power? With respect to the Reed-Elsevier/Pergamon transaction the answer seems clear. Post-merger (1992-1998), Elsevier journal prices were unchanged but the former Pergamon titles experienced a 27% increase. This asymmetry is observed in the Kluwer-Lippincott merger as well. Post-merger, the former Lippincott titles experienced a 30% price increase while the Kluwer prices were unchanged. However, in this case the Lippincott price increase is not solely a consequence of enhanced market power. The results suggest that demand for Lippincott titles became slightly more inelastic in the post-merger period, contributing at least partially to the observed 30% price increase.