Understanding constraints on non-projectivity using novel measures Himanshu Yadav1 1 Jawaharlal 2 Indian
Ashwini Vaidya2
Samar Husain2
Nehru University, New Delhi, India
Institute of Technology Delhi, India
International Conference on Dependency Linguistics Pisa, Italy. September 18-20, 2017
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Motivation ROOT
ROOT
mohan=kii mohan=GEN
kal yesterday
kitaab book
kho gayii lose go.Perf
mohan=kii mohan=GEN
Acceptable
do din pahle two day ago
scootar=se scooter=INS
school school
jaate hue go be.NF
kitaab book
kho gayii lose go.Perf
Odd
ROOT ROOT
mohan=kii mohan=GEN
nahin not
kitaab book
khoyii lose.Perf
mohan=kii mohan=GEN
raam=ko raam=DAT
kitaab book
Odd
Ungrammatical
2
kho jaane ka lose go.NF
dukh hai sad be.Present
Proposed measures Intervener Length • Number of words between the dependent (Xd ) and the head (Xd ) of the non-projective arc such that they are not dominated by (Xh ).
Xd
Xi
Xh
Xj
Intervener length = size of the intervening constituent (Xi ).
1. Intervener type 2. Intervener length 3. Depth difference 3
Proposed measures cont. ROOT ROOT
mohan=kii mohan=GEN
kal yesterday
kitaab book
mohan=kii mohan=GEN
kho gayii lose go.Perf
Acceptable (Edge degree=1, Intervener length=1, Intervener type=NP, Depth difference=1)
do din pahle two day ago
scootar=se scooter=INS
school school
jaate hue go be.NF
kitaab book
kho gayii lose go.Perf
Odd (Edge degree=1, Intervener length=8, Intervener type=VGNF, Depth difference=1)
ROOT
ROOT
mohan=kii mohan=GEN
nahin not
kitaab book
khoyii lose.Perf
Ungrammatical (Edge degree=1, Intervener length=1, Intervener type=NEGP, Depth difference=1)
mohan=kii mohan=GEN
raam=ko raam=DAT
kitaab book
kho jaane ka lose go.NF
dukh hai sad be.Present
Odd (Edge Degree=1, Intervener length=2, Intervener type=NP, Depth difference=2) 4
Results
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Summary
• Although certain linguistic phenomenon can become non-projective, the range of allowed non-projective configurations is limited. • This limitation is influenced by interaction between processing constraints and syntactic complexity. • We have shown using three novel measures that non-projective configurations tend to be simple than complex.
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