What Divides, and What Unites, Right-Node Raising

We argue, following Barros and Vicente (2011), that right-node raising (RNR) results from either ellipsis or multidominance. Four considerations support this claim. (i) RNR has properties of ellipsis and of multidominance. (ii) Where these are combined, the structure results from repeated RNR: a pivot created through ellipsis contains a right-peripheral secondary pivot created through multidominance. (iii) In certain circumstances, one or the other derivation is blocked, so that RNR behaves like pure ellipsis or pure multidominance. (iv) Linearization of RNR-as-multidominance requires pruning. The same pruning operation delivers RNR-as-ellipsis, which explains why the two derivations must meet the same ordering constraints.

Not all wh-dependencies are created equal: processing of multiple wh-questions in Romanian children and adults

The aim of this study was to examine the acquisition and processing of multiple who- and which-questions in Romanian that display ordering constraints and involve exhaustivity. Toward that aim, typically developing Romanian children (mean age 8.3) and adults participated in a self-paced listening experiment that simultaneously investigated online processing and offline comprehension of multiple wh-questions. The study manipulated the type of wh-phrase (who/which) and the order in which these elements appear (subject–object [SO]/object–subject [OS]). The response to the comprehension question could address the issue of exhaustivity because we measured whether participants used an exhaustive or a non-exhaustive response. Our findings reveal that both children and adults slow down when processing who- as compared to which-phrases, but only adults show an online sensitivity to ordering constraints in who-questions. Accuracy is higher with multiple who- than which-questions. The latter pose more difficulties for comprehension, particularly in the OS order. We relate this to intervention effects similar to those proposed for single which-questions. The lack of intervention effects in terms of reaction times indicates that these effects occur at a later stage, after participants have heard the whole sentence and when they interpret its meaning.

PETRA

Emerging byte-addressable Non-Volatile Memories (NVMs) enable persistent memory where process state can be recovered after crashes. To enable applications to rely on persistent data, durable data structures with failure-atomic operations have been proposed. However, they lack the ability to allow users to execute a sequence of operations as transactions. Meanwhile, persistent transactional memory (PTM) has been proposed by adding durability to Software Transactional Memory (STM). However, PTM suffers from high performance overheads and low scalability due to false aborts, logging, and ordering constraints on persistence. In this article, we propose PETRA, a new approach for constructing persistent transactional linked data structures. PETRA natively supports transactions, but unlike PTM, relies on the high-level information from the data structure semantics. This gives PETRA unique advantages in the form of high performance and high scalability. Our experimental results using various benchmarks demonstrate the scalability of PETRA in all workloads and transaction sizes. PETRA outperforms the state-of-the-art PTMs by an order of magnitude in transactions of size greater than one, and demonstrates superior performance in transactions of size one.

Restrictions on ordering of adjectives in Spanish

Sequences of multiple modifying adjectives are subject to poorly understood lexical ordering restrictions. There are certain commonalities to these restrictions across languages, as well as substantive language variation. Ordering restrictions in Spanish are still under empirical debate, with some proposing strict ordering for direct modifier adjectives; others proposing broad ordering restrictions based on the contrast between intersective and non-intersective adjectives, and yet others raising the possibility that adjectival order is fully unrestricted. The goal of the present study is to examine corpus evidence for adjectival sequences. We look at both sequences of two postnominal adjectives (Noun +Adjective + Adjective, NAA sequences) as well as sequences of one prenominal, and one postnominal adjective (Adjective + Noun +Adjective, ANA sequences). The results from the NAA datasets clearly categorically confirms that relational adjectives are structurally closer to the noun. There is some evidence for an ordering bias along the line of the intersectivity hypothesis, but little else in term of hard evidence for restrictions. Additional ordering constraints appear once we incorporate the ANA datasets into the empirical picture. One interpretation is that these restrictions can be subsumed under an approach where evaluative adjectives have to occupy the prenominal restriction. In sum, the evidence is most compatible with the middle ground approach, but not with a fully articulated set of ordering restrictions.

POP ≡ POCL, Right? Complexity Results for Partial Order (Causal Link) Makespan Minimization

We study PO and POCL plans with regard to their makespan – the execution time when allowing the parallel execution of causally independent actions. Partially ordered (PO) plans are often assumed to be equivalent to partial order causal link (POCL) plans, where the causal relationships between actions are explicitly represented via causal links. As a first contribution, we study the similarities and differences of PO and POCL plans, thereby clarifying a common misconception about their relationship: There are PO plans for which there does not exist a POCL plan with the same orderings. We prove that we can still always find a POCL plan with the same makespan in polynomial time. As another main result we prove that turning a PO or POCL plan into one with minimal makespan by only removing ordering constraints (called deordering) is NP-complete. We provide a series of further results on special cases and implications, such as reordering, where orderings can be changed arbitrarily.