scholarly journals Industry standard and econometric standard: the search for powerful approach to evaluate var models

2021 ◽  
Vol 2021 (1) ◽  
pp. 5-30
Author(s):  
Marta Małecka
2020 ◽  
Vol 492 (3) ◽  
pp. 3960-3983 ◽  
Author(s):  
V M Rajpaul ◽  
S Aigrain ◽  
L A Buchhave

ABSTRACT Doppler spectroscopy is a powerful tool for discovering and characterizing exoplanets. For decades, the standard approach to extracting radial velocities (RVs) has been to cross-correlate observed spectra with a weighted template mask. While still widely used, this approach is known to suffer numerous drawbacks, and so in recent years increasing attention has been paid to developing new and improved ways of extracting RVs. In this proof-of-concept paper, we present a simple yet powerful approach to RV extraction. We use Gaussian processes to model and align all pairs of spectra with each other; we combine the pairwise RVs thus obtained to produce accurate differential stellar RVs, without constructing any template. Doing this on a highly localized basis enables a data-driven approach to identifying and mitigating spectral contamination, even without the input of any prior astrophysical knowledge. We show that a crude implementation of this method applied to an inactive standard star yields RVs with comparable precision to and significantly lower rms variation than RVs from industry-standard pipelines. Though amenable to numerous improvements, even in its basic form presented here our method could facilitate the study of smaller planets around a wider variety of stars than has previously been possible.


2017 ◽  
pp. 88-110 ◽  
Author(s):  
S. Drobyshevsky ◽  
P. Trunin ◽  
A. Bozhechkova ◽  
E. Gorunov ◽  
D. Petrova

The article investigates the Bank of Russia information policy using a new approach to measuring information effects on Russian data, including the analysis of the tonality of news reports, as well as internet users’ queries on Google. The efficiency of regulator’s information signals is studied using EGARCH-, VAR- models, as well as nonparametric tests. The authors conclude that the regulator communicates effectively in terms of the predictability of interest rate policy, the degree to which information signals affect the money and foreign exchange markets.


2018 ◽  
Author(s):  
Suresh Natarajan ◽  
Cara-Lena Nies ◽  
Michael Nolan

<div>As the critical dimensions of transistors continue to be scaled down to facilitate improved performance and device speeds, new ultrathin materials that combine diffusion barrier and seed/liner properties are needed for copper interconnects at these length scales. Ideally, to facilitate coating of high aspect ratio structures, this alternative barrier+liner material should only consist of one or as few layers as possible. We studied TaN, the current industry standard for Cu diffusion barriers, and Ru, which is a</div><div>suitable liner material for Cu electroplating, to explore how combining these two materials in a barrier+liner material influences the adsorption of Cu atoms in the early stage of Cu film growth. To this end, we carried out first-principles simulations of the adsorption and diffusion of Cu adatoms at Ru-passivated and Ru-doped e-TaN(1 1 0) surfaces. For comparison, we also studied the behaviour of Cu and Ru adatoms at the low index surfaces of e-TaN, as well as the interaction of Cu adatoms with the (0 0 1) surface of hexagonal Ru. Our results confirm the barrier and liner properties of TaN and Ru, respectively while also highlighting the weaknesses of both materials. Ru passivated TaN was found to have improved binding with Cu adatoms as compared to the bare TaN and Ru surfaces.</div><div>On the other hand, the energetic barrier for Cu diffusion at Ru passivated TaN surface was lower than at the bare TaN surface which can promote Cu agglomeration. For Ru-doped TaN however, a decrease in Cu binding energy was found in addition to favourable migration of the Cu adatoms toward the doped Ru atom and unfavourable migration away from it or into the bulk. This suggests that Ru doping sites in the TaN surface can act as nucleation points for Cu growth with high migration barrier preventing agglomeration and allow electroplating of Cu. Therefore Ru-doped TaN is proposed as a candidate for a combined barrier+liner material with reduced thickness.</div>


2020 ◽  
Vol 10 (1) ◽  
pp. 12
Author(s):  
Ekka Pujo Ariesanto Akhmad

<strong> </strong>Bagian pemasaran bank sudah menampung data dari nasabah atau pelanggan bank dengan cara memasarkan atau mensosialisasikan kartu kredit lewat telepon (telemarketing). Evaluasi telemarketing kartu kredit yang sudah dilakukan bank masih kurang membawa hasil dan berdaya guna. Salah satu cara yang tepat untuk evaluasi laporan telemarketing kartu kredit bank adalah menggunakan teknik data mining. Tujuan penggunaan data mining untuk mengetahui kecenderungan dan pola nasabah yang berpeluang untuk berlangganan kartu kredit yang ditawarkan bank. Metode penelitian menggunakan Cross Industry Standard Process for Data Mining (CRISP-DM) dengan Algoritma Genetika untuk Seleksi Fitur (GAFS) dan Naive Bayes (NB). Hasil penelitian menunjukkan jumlah atribut pada dataset telemarketing kartu kredit bank sejumlah 15 atribut terdiri dari 14 atribut biasa dan 1 atribut spesial. Dataset telemarketing bank mengandung data berdimensi tinggi, sehingga diterapkan metode GAFS. Setelah menerapkan metode GAFS diperoleh 7 atribut optimal terdiri dari 6 atribut biasa dan 1 atribut spesial. Enam atribut biasa meliputi pekerjaan, balance, rumah, pinjaman, durasi, poutcome. Sedangkan atribut spesial adalah target. Hasil penelitian menunjukkan algoritma NB mempunyai nilai akurasi <em>86,71</em>%. Algoritma GAFS dan NB meningkatkan nilai akurasi menjadi <em>90,27</em>% untuk prediksi nasabah bank yang mengambil kartu kredit.


Author(s):  
Ian Kearney ◽  
Stephen Brink

Abstract The shift in power conversion and power management applications to thick copper clip technologies and thinner silicon dies enable high-current connections (overcoming limitations of common wire bond) and enhance the heat dissipation properties of System-in-Package solutions. Powerstage innovation integrates enhanced gate drivers with two MOSFETs combining vertical current flow with a lateral power MOSFET. It provides a low on-resistance and requires an extremely low gate charge with industry-standard package outlines - a combination not previously possible with existing silicon platforms. These advancements in both silicon and 3D Multi-Chip- Module packaging complexity present multifaceted challenges to the failure analyst. The various height levels and assembly interfaces can be difficult to deprocess while maintaining all the critical evidence. Further complicating failure isolation within the system is the integration of multiple chips, which can lead to false positives. Most importantly, the discrete MOSFET all too often gets overlooked as just a simple threeterminal device leading to incorrect deductions in determining true root cause. This paper presents the discrete power MOSFET perspective amidst the competing forces of the system-to-board-level failure analysis. It underlines the requirement for diligent analysis at every step and the importance as an analyst to contest the conflicting assumptions of challenging customers. Automatic Test Equipment (ATE) data-logs reported elevated power MOSFET leakage. Initial assumptions believed a MOSFET silicon process issue existed. Through methodical anamnesis and systematic analysis, the true failure was correctly isolated and the power MOSFET vindicated. The authors emphasize the importance of investigating all available evidence, from a macro to micro 3D package perspective, to achieve the bona fide path forward and true root cause.


2007 ◽  
Vol 9 (2) ◽  
pp. 39-54 ◽  
Author(s):  
Victor de la Pena ◽  
Ricardo Rivera ◽  
Jesus Ruiz-Mata

2003 ◽  
Author(s):  
Christian C.P. Wolff ◽  
Dennis Bams ◽  
Thorsten Lehnert

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