5.2.1.2 Cumulative Change of Research Productivity Relative to Base
Year 2006
To further explore the differences on the cumulative effect caused by yearly
research productivity changes between 985Us and non-985Us, in this subsection we
set 2006 as the base year, in order to analyze the cumulative changes of TFP index
and its decomposition relative to 2006.^6 Figure5.4plots cumulative yearly changes
of TFP indexes in both groups relative to 2006 in line chart.
It’s obvious that TFP indexes of NEAM disciplines in both groups are growing
cumulatively from 2006 to 2010. NEAM disciplines of non-985Us show stronger
growth in 2006–2010 relative to base year, with afive-year cumulative growth rate
as large as 41.3%. Compared with non-985Us, the 985Us merely shows a strong
growth in 2008–2009, while its growths in 2006–2007, 2007–2008, 2009–2010 are
not so obvious. Relative to the base year, thefive-year cumulative growth rate of
TFP index of 985Us is 11.9%.
In the next step, we analyze the cumulative changes of TEC index, TC index,
PTEC index and SEC index in the same way, aiming for clarifying the main sources
of cumulative changes of TFP index. The results are plotted in Fig.5.5.
Overall speaking, from 2006 to 2010, cumulative changes of NEAM research
productivities in both groups are in the same trend, namely the cumulative changes
of each decomposition index is rather stable. However, except the growth effect
indicated by TC index are increased cumulatively and consistently in this phase,
neither of the other indexes shows any substantially cumulative growth relative to
the base year. Thisfinding confirms that growth effect is the absolute source of
Fig. 5.3 Research productivity and its decomposition of 985Us and non-985Us (NEAM)
(^6) The cumulative growth rate of the jth research productivity index cumulative toTyear can be
computed by:MTj¼PTt¼ 2006 mtj,mtjindicates the average of thejth index in the t year.
5.2 Differences and Trends on Research Productivity of 985Us and Non-985Us 227