Foxboro B0132WM-E CPU Board Module PLC B0132WME SN1323 2RVRS Measurex Honeywell
Foxboro B0132WM-E CPU Board Module PLC B0132WME SN1323 2RVRS Measurex Honeywell
CPU Board Module PLC B0132WME SN1323 2RVRS Measurex Honeywell
CPU Board Module PLC B0132WME SN1323 2RVRS Measurex Honeywell中國工業(yè)企業(yè)數(shù)據(jù)庫的使用現(xiàn)狀和潛在問題聶輝華江艇楊汝岱內(nèi)容提要在經(jīng)驗研究中，企業(yè)級的微觀數(shù)據(jù)正受到越來越多的重視。中國工業(yè)企業(yè)數(shù)據(jù)庫成為國內(nèi)外學(xué)者研究中國企業(yè)行為和績效的主要數(shù)據(jù)庫之一。
但是該數(shù)據(jù)庫存在樣本匹配混亂、變量大小異常、測度誤差明顯和變量定義模糊等嚴(yán)重問題，忽視這些問題可能會導(dǎo)致研究結(jié)論錯誤。本文介紹了該數(shù)據(jù)庫的基本情況和使用現(xiàn)狀，指出了該數(shù)據(jù)庫存在的缺陷，并根據(jù)現(xiàn)有研究提出了改進建議。
一引言數(shù)據(jù)是經(jīng)驗研究的細胞，因此數(shù)據(jù)質(zhì)量的好壞直接決定了經(jīng)驗研究的活力。zui近十多年來，經(jīng)濟學(xué)界越來越重視使用微觀面板數(shù)據(jù)longitudinal micro－level da ta的研究。相對于宏觀數(shù)據(jù)或行業(yè)數(shù)據(jù)，微觀的企業(yè)數(shù)據(jù)或個體數(shù)據(jù)的優(yōu)勢是非常明顯的：*，微觀面板數(shù)據(jù)包含了更多信息，例如企業(yè)的所有制、規(guī)模和出口等狀態(tài)，這些信息對于企業(yè)行為的研究*；第二，微觀面板數(shù)據(jù)同時包含了時間維度和個體維度，有助于解決計量經(jīng)濟學(xué)中的個體異質(zhì)性問題，更容易保證估計的*性；
KOLON POWER SUPPLY IC693PWR321K MANUFACTURED UNDER LICENCE GE FANUC
OMRON PLC MODULES C200H-ID215 C200H-ID212 C200H-OC222 C200H-OC225
MITSUBISHI CC-LINK INPUT/ OUTPUT UNITS AJ65SBTB1-32D AJ65SBTB1-32T
SANYO DENKI BL SUPER ROBUSTSYN RBD2C-202
FESTO VALVE TYPE DSR-12-180-P
HONEYWELL MICRO SWITCH GKNC21 NEW NOT IT BOX LOT OF 6
HONEYWELL MICRO SWITCH GKNC30 NEW NOT IT BOX LOT OF 6
AUTONICS MULTI METER MT4Y-AA-4N LOT OF TWO
AUTONICS MULTI METER MT4Y-AV-4N LOT OF TWO
AUTONICS MULTI METER MT4Y-DV-41 LOT OF TWO
WEST N6100 TEMPERATURE CONTROLLER
GE FANUC PLC IC693MDL752E OUTPUT TTL 32PT WORKING
HANYOUNG DX2 TEMP. CONTROLLER DX2_KSWNR -50'C TO 1300'C LOT OF 2
HANYOUNG DX2 TEMP. CONTROLLER KSWNR KSC 1613 -50'C TO 1300'C LOT OF 2
RED LION DC MONITOR M2444B
GE FANUC PLC MODULE- IC655MDL512B INPUT MODULE 32 CIRCUITS NO SIDE COVER
FUJIKIN DIAHPRAGM VALVE LOT OF 4 TWO 067645 TWO 038818 INLET OUTLET DIA. 1/4in
OMRON S8PS-10024 POWER SUPPLY TESTED WORKING
HILSCHER GMBH DEVICENET PCI CARD CIF50-DNM, CIF50 BSL-DN V1.503
GE FANUC POWER SUPPLY IC693PWR321S TESTED WORKING, FREE SHIPPING!
SIEMENS SIMATIC,S7 1P 6ES7 -307-1BA00-0AA0
SIEMENS SIMATIC, 6ES5430-4UA13
OMRON SYSMAC MINI SK20 PROGRAMMABLE CONTROLLER SK20-C2DR-D PLC
MITSUBISHI AC SERVO DRIVE MR-C10A1 100W
SHIMADEN CONVERTER CP2MD-4613-0
SMC MGPM25-40 Compact Guide Cylinder
MOORE INDUSTRIES IPT2/4-20MA/3-27PSIG/35PSI-FA1 [DIN]
MOORE INDUSTRIES IPT2/4-20MA/3-27PSIG/35PSI-FA7 [DIN]
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