From the 203 firms there are 250 responses. Each respondent was asked for the name of the unit for which they were responding so that a check could be made that multiple responses were not being received from the same decision-making unit. Of the 250 responses, 76 (30.4 percent) were from business units and 174 (69.9 percent) were responding for a corporate R&D unit. There is no way to determine whether a non-respondent would have answered for a business unit or for a corporate R&D unit.

Results of statistical tests are presented in the text and below the figures. With the exception of the test reported for the comparison of the data in Figure 5, all tests are standard tests of equality of means. It is assumed that variances are unequal and observations are not paired. Alternative tests would consider whether distributions of responses are significantly different. Since the comparisons in the figures and the discussion in the text are for differences of means, the tests are tests of equality of means rather than distributions. The statistical test reported for the data in Figure 5 is Pearson’s chi-square test of whether the distributions of years for sites inside and sites outside are significantly different.

The level of significance reported for tests is the largest significance level at which the null hypothesis of no difference is rejected. Thus, if it is reported that a group of comparisons are significantly different at the 5-percent level, then every test statistic has a p-value of 0.05 or less. Some might be less than 0.01 (that is, a 1-percent significance level). If differences are reported as not being significantly different, then a significance level of 5 percent has been used.

The number of respondents answering questions is presented below most figures. This is typically a range since the figures are drawn from a number of questions. Thus, for example, below Figure 4 it is reported that there are 223–230 respondents, indicating that a minimum of 223 respondents answered each of the seven questions in Figure 4 and for some questions there were 230 respondents.

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