Second, aggregate information provides only a high-level view of a field, which can make it difficult to investigate causality [23].
1	Second	second	ADV	RB	Degree=Pos|NumType=Ord	5	advmod	5:advmod	Discourse=joint-list_m:64->61:2|SpaceAfter=No
2	,	,	PUNCT	,	_	1	punct	1:punct	_
3	aggregate	aggregate	ADJ	JJ	Degree=Pos	4	amod	4:amod	Entity=(146-abstract-new-cf3-2-sgl
4	information	information	NOUN	NN	Number=Sing	5	nsubj	5:nsubj	Entity=146)
5	provides	provide	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	0:root|18:csubj	_
6	only	only	ADV	RB	_	11	advmod	11:advmod	_
7	a	a	DET	DT	Definite=Ind|PronType=Art	11	det	11:det	Entity=(147-abstract-new-cf4-5-sgl
8	high	high	ADJ	JJ	Degree=Pos	10	amod	10:amod	SpaceAfter=No|XML=<w>
9	-	-	PUNCT	HYPH	_	8	punct	8:punct	SpaceAfter=No
10	level	level	ADJ	JJ	Degree=Pos	11	amod	11:amod	XML=</w>
11	view	view	NOUN	NN	Number=Sing	5	obj	5:obj	_
12	of	of	ADP	IN	_	14	case	14:case	_
13	a	a	DET	DT	Definite=Ind|PronType=Art	14	det	14:det	Bridge=60<148|Entity=(148-object-acc:inf-cf1-2-sgl
14	field	field	NOUN	NN	Number=Sing	11	nmod	11:nmod:of	Entity=148)147)|SpaceAfter=No
15	,	,	PUNCT	,	_	18	punct	18:punct	_
16	which	which	PRON	WDT	PronType=Rel	18	nsubj	5:ref|18:nsubj	Discourse=elaboration-additional:65->64:0
17	can	can	AUX	MD	VerbForm=Fin	18	aux	18:aux	_
18	make	make	VERB	VB	VerbForm=Inf	5	advcl:relcl	5:advcl:relcl	_
19	it	it	PRON	PRP	Case=Acc|Gender=Neut|Number=Sing|Person=3|PronType=Prs	18	obj	18:obj|20:nsubj:xsubj	Entity=(149-abstract-new-cf2-1-cata)
20	difficult	difficult	ADJ	JJ	Degree=Pos	18	xcomp	18:xcomp	_
21	to	to	PART	TO	_	22	mark	22:mark	Entity=(149-abstract-acc:com-cf2-2-coref
22	investigate	investigate	VERB	VB	VerbForm=Inf	20	xcomp	20:xcomp	_
23	causality	causality	NOUN	NN	Number=Sing	22	obj	22:obj	Entity=(150-abstract-new-cf5-1-sgl)149)
24	[	[	PUNCT	-LRB-	_	25	punct	25:punct	Discourse=explanation-evidence:66->64:1|SpaceAfter=No
25	23	23	NUM	CD	NumForm=Digit|NumType=Card	5	dep	5:dep	Entity=(151-abstract-new-cf6-1-sgl)|SpaceAfter=No|XML=<ref></ref>
26	]	]	PUNCT	-RRB-	_	25	punct	25:punct	SpaceAfter=No
27	.	.	PUNCT	.	_	5	punct	5:punct	_
