Cluster policy: insights from the German leading edge cluster competition

Table 1 Group comparison after matching (LECC funded vs. non-funded, mean values)

Outcome variable	LECC-funded	Non-funded	ATT_DiD	t-test		#
All companies (2007–2011)
CGR R&D expenditures	0.45^a	−0.138	0.588	3.39	^***	135
CGR internal R&D expend.	0.403	−0.122	0.525	2.99	^***	110
CGR external R&D expend.	0.42	0.565	−0.145	0.43		109
CGR R&D personnel	0.279	0.022	0.257	2.14	^**	72
Δ R&D exp./employees	5.681	−0.229	5.91	2.56	^**	134
Δ R&D exp./turnover	0.143	−2.555	2.698	1.22		135
Δ internal R&D exp./turnover	−1.67	−2.204	0.534	0.25		110
Δ external R&D exp./turnover	1.26	−0.35	1.61	1.85	^*	110
SME only (2007–2011)
CGR R&D expenditures	0.576	−0.197	0.774	3.74	^***	80
CGR internal R&D expend.	0.552	−0.217	0.77	3.36	^***	57
CGR external R&D expend.	0.624	−0.26	0.884	2.74	^***	57
CGR R&D personnel	0.295	−0.064	0.359	2.63	^***	48
Δ R&D exp./employees	6.155	−3.269	9.424	2.81	^***	79
Δ R&D exp./turnover	−0.943	−4.941	3.998	1.12		80
Δ internal R&D exp./turnover	−4.273	−5.096	0.823	0.22		57
Δ external R&D exp./turnover	1.901	−1.183	3.084	1.96	^**	57

Discrete change (Δ) or continuous growth rate (CGR) of mean values. ^a The value 0,45 means an 45% increase. ATT_DiD: difference between mean values in column 2 and 3. # number of observations. ^* p < 0.10, ^** p < 0.05, ^*** p < 0.01. For a more detailed description of the method and variables see Engel et al. (2017)