Free Entry and Social Inefficiency under Co-opetition

We investigate the social desirability of free entry in the co-opetition model in which firms compete in a homogeneous product market while sharing common property resources that affect consumers' willingness to pay for products. Our findings show that free entry leads to socially excessive or insufficient market entry in the case of non-commitment co-opetition, depending on the magnitude of "business stealing" and "common property" effects of entry. On the other hand, in the case of pre-commitment co-opetition, free entry leads to excess entry and a decline in common property resources. Interestingly, in this case, the excess entry results of Mankiw and Whinston (1986) and Suzumura and Kiyono (1987) hold even when there are no entry (set-up) costs. These results have important policy implications for entry regulation

Free Entry and Social Inefficiency under Co-opetition

We investigate the social desirability of free entry in the co-opetition model in which firms compete in a homogeneous product market while sharing common property resources that affect market size or consumers' willingness to pay for products. We show that free entry leads to socially excessive or insufficient entry into the market in the case of non-commitment co-opetition, depending on the magnitude of "business stealing" and "common property" effects of entry. On the other hand, in the case of pre-commitment co-opetition, free entry leads to excess entry and a decline in the common property resources. Interestingly, in the latter case, the excess entry result of Mankiw and Whinston (1986) and Suzumura and Kiyono (1987) holds even when there are no entry (set-up) costs for entrants. These results have important policy implications for entry regulations

Free Entry and Social Inefficiency under Co-opetition

We investigate the social desirability of free entry in the co-opetition model in which firms compete in a homogeneous product market while sharing common property resources that affect market size or consumers' willingness to pay for products. We show that free entry leads to socially excessive or insufficient entry into the market in the case of non-commitment co-opetition, depending on the magnitude of "business stealing" and "common property" effects of entry. On the other hand, in the case of pre-commitment co-opetition, free entry leads to excess entry and a decline in the common property resources. Interestingly, in the latter case, the excess entry result of Mankiw and Whinston (1986) and Suzumura and Kiyono (1987) holds even when there are no entry (set-up) costs for entrants. These results have important policy implications for entry regulations

Empirical Investigation of Neural Symbolic Reasoning Strategies

Neural reasoning accuracy improves when generating intermediate reasoning steps. However, the source of this improvement is yet unclear. Here, we investigate and factorize the benefit of generating intermediate steps for symbolic reasoning. Specifically, we decompose the reasoning strategy w.r.t. step granularity and chaining strategy. With a purely symbolic numerical reasoning dataset (e.g., A=1, B=3, C=A+3, C?), we found that the choice of reasoning strategies significantly affects the performance, with the gap becoming even larger as the extrapolation length becomes longer. Surprisingly, we also found that certain configurations lead to nearly perfect performance, even in the case of length extrapolation. Our results indicate the importance of further exploring effective strategies for neural reasoning models.Comment: This paper is accepted as the findings at EACL 2023, and the earlier version (non-archival) of this work got the Best Paper Award in the Student Research Workshop of AACL 202

Do Deep Neural Networks Capture Compositionality in Arithmetic Reasoning?

Compositionality is a pivotal property of symbolic reasoning. However, how well recent neural models capture compositionality remains underexplored in the symbolic reasoning tasks. This study empirically addresses this question by systematically examining recently published pre-trained seq2seq models with a carefully controlled dataset of multi-hop arithmetic symbolic reasoning. We introduce a skill tree on compositionality in arithmetic symbolic reasoning that defines the hierarchical levels of complexity along with three compositionality dimensions: systematicity, productivity, and substitutivity. Our experiments revealed that among the three types of composition, the models struggled most with systematicity, performing poorly even with relatively simple compositions. That difficulty was not resolved even after training the models with intermediate reasoning steps.Comment: accepted by EACL 202

臥床早期の下肢水分移行はHUSを減少させる

OBJECTIVE: To investigate whether or not the leg fluid displacement observed when moving from the standing to recumbent position at bedtime reduces the hours of undisturbed sleep (HUS). METHODS: Men aged 50 years or older who were hospitalized for urological diseases were investigated. Body water evaluation was performed three times with a bioelectric impedance method: (i) 17:00, (ii) 30 min after (short-term), and (iii) waking up (long-term). A frequency volume chart was used to evaluate the status of nocturnal urine production, and the factors affecting HUS were investigated. RESULTS: A total of 50 patients (mean age: 68 years) were enrolled. Short-term changes in extracellular fluid (ECF in the legs showed a significant positive correlation with urine production per unit of time at the first nocturnal voiding (UFN/HUS) (r = 0.45, P = 0.01). In the comparison between patients who had <3 HUS vs. those who had ≥3 HUS, the <3 HUS group showed significantly greater short-term changes in leg fluid volume, night-time water intake (17:00-06:00), and UFN/HUS. Multivariate analysis to assess the risk factors for <3 HUS indicated UFN/HUS as a risk factor in the overall model, and short-term changes in leg ECF and night-time water intake as risk factors in the model that only considered factors before sleep. CONCLUSIONS: Nocturnal leg fluid displacement may increase urine production leading up to first voiding after going to bed, and consequently, induce early awakening after falling asleep.博士（医学）・甲第703号・平成31年3月15日© 2017 John Wiley & Sons Australia, LtdThis is the pre-peer reviewed version of the following article: [https://onlinelibrary.wiley.com/doi/10.1111/luts.12176], which has been published in final form at [http://dx.doi.org/10.1111/luts.12176]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions