Group1	Group2	Group1 mean	Group1 std	Group2 mean	Group2 std	t stat	p-value
firm	NA	3.45983843721	0.465827008191	4.10027767533	0.26750179267	-2.82340472704	0.03
NA	bact	4.10027767533	0.26750179267	3.9740340295	0.530621853475	0.512854608451	1.0
firm	bact	3.45983843721	0.465827008191	3.9740340295	0.530621853475	-3.57710996553	0.003
