There Is Nothing Outside the Text, and There Is No Safety in Numbers: A Reply to Sullivan
回应Sullivan，指出历史学家和经济学家需要指数来衡量创新活动（研发支出）和成果（发明数量），但1914年前的研发支出数据极少，难以构建指数。
Historians and economists have long been in need of index numbers to measure both the volume (real value) of activity that is undertaken to produce process or product innovations over time, and also a counterpart index that might capture the outcome of that activity (the volume of inventions) that come on stream year after year. For purposes of measurement the first index can in principle be equated (within tolerable limits of accuracy) with the real annual expenditures on research and development as recorded (at least for recent times) in governmental, corporate, company, and other accounts. Alas, for years before 1914 national or even industry-wide research and development expenditures are very rarely recorded in a form that might allow for the construction of an index number.