The Output Contributions of Computer Equipment and Personnel: A Firm- Level Analysis

This paper examines the output contributions of capital and labor deployed in information systems (IS) at the firm level during the period 1988-91 throughout the business sector, using two different sources of data on these inputs. Our production function estimates suggest that there are substantial excess returns to both IS capital and IS labor, although the size and significance of the excess returns to IS capital is larger. Computer capital and labor jointly contribute, or account for, about 21 percent of output, although only about 10% of both capital and labor income accrue to IS factors. Although IS employees accounted for a very small share of total employment by 1986, IS employment growth is estimated to have made a larger contribution to 1976-86 output growth than non-IS employment, due to the very rapid growth (16% per annum) of IS employment. The estimated marginal rate of substitution (MRS) between IS and non-IS employees, evaluated at the sample mean, is 6: one IS employee can be substituted for six non-IS employees without affecting output.