서명환 교수

In this article, we develop a command, xthenreg, that implements the first-differenced generalized method of moments estimation of the dynamic panel threshold model that Seo and Shin (2016, Journal of Econometrics 195: 169–186) proposed. Furthermore, we derive the asymptotic variance formula for a kink-constrained generalized method of moments estimator of the dynamic threshold model and provide an estimation algorithm. We also propose a fast bootstrap algorithm to implement the bootstrap for th

Using the Reinhart-Rogoff dataset, we find a debt threshold not around 90 per cent but around 30 per cent, above which the median real gross domestic product (GDP) growth falls abruptly. Our work is the first to formally test for threshold effects in the relationship between public debt and median real GDP growth. The null hypothesis of no threshold effect is rejected at the 5 per cent significance level for most cases. While we find no evidence of a threshold around 90 per cent, our findings fr

The INV angle of the Asians measured by CT scan was 21.6 degrees +/-4.5 degrees . This value was significantly larger than that of the Caucasians, which has been reported to be 11.4 degrees +/-2.6 degrees (p<0.001). The INV angle measured endoscopically was 19.3 degrees +/-3.6 degrees . Reproducibility of the reconstructed CT method was good (p<0.001), while the reproducibility of the endoscopic method was poor (p=0.093). The correlation between the two methods was also poor (p=0.107).

Slippage-induced artifacts are presumed to be because of the slingshot-like movement of the goggles during head movement in three different phases (lagging, overshooting, and bouncing of the goggles). Monitoring the pressure of the strap tightness may be a solution for minimizing this slippage. A strap tightness of at least 45 cm H2O is required for reliable vHIT recording and gain calculations.

The risk factors for MT may be an age of over 45 yr and multiple recurrences. However, younger patients are more at risk of recurrence. A clear resection margin cannot guarantee a cure in RPA, and it seems that parotid pleomorphic adenomas slowly gain malignant characteristics after repeated recurrences.

The 10-20 EEG coordinates of the AC in Asians were significantly different to those in Caucasians. To accurately aim for the AC in Asians, it is recommended that the rTMS be located 1.8 cm superior to the T3 and 0.6 cm posterior to the T3-Cz line. However, because the spatial resolution of the TMS is rather low, this difference probably was not reflected in the treatment outcome.

We examine the asymptotic properties of local M-estimators under three sets of high-level conditions. These conditions are sufficiently general to cover the minimum volume predictive region, the conditional maximum score estimator for a panel data discrete choice model and many other widely used estimators in statistics and econometrics. Specifically, they allow for discontinuous criterion functions of weakly dependent observations which may be localized by kernel smoothing and contain nuisance

Speechreading is a visual communicative skill for perceiving speech. In this study, we tested the effects of speech experience and deafness on the speechreading neural network in normal hearing controls and in two groups of deaf patients who became deaf either before (prelingual deafness) or after (postlingual deafness) auditory language acquisition. Magnetic signals from the cerebral cortex were recorded using a 306-channel magnetoencephalographic system. During magnetoencephalographic measurem