11.6 Company-financed expenditures in manufacturing on research and development (R&D) are currently about 2.7% of sales in Japan and 2.8% of sales in the United States. However, when these figures are looked at separately according to industry, the following data from Mansfield (1989) show some large differences.

Industry Japan United States Food 0.8 0.4 Textiles 1.2 0.5 Paper 0.7 1.3 Chemicals 3.8 4.7 Petroleum 0.4 0.7 Rubber 2.9 2.2 Ferrous metals 1.9 0.5 Nonferrous metals 1.9 1.4 Metal products 1.6 1.3 Machinery 2.7 5.8 Electrical equipment 5.1 4.8 Motor vehicles 3.0 3.2 Other transport equipment 2.6 1.2 Instruments 4.5 9.0

(a) Use the signed-rank test of Chapter 5 to determine whether Japan spends a larger percentage than the United States on R&D.

(b) Determine whether there is a significant positive relationship between percentages spent by Japan and the United States (use two different methods).