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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

藉由小世界股票網路探索不同景氣區間的差異性 / Exploring economy-realated differences by small-world stock networks

邱建堯, Chiu, Chien Yao Unknown Date (has links)
股票市場對投資者而言是以極大化自有資產為目的,因此如何辨別不同景氣區間對股市的影響為投資者感興趣的議題。傳統上,使用統計資料來幫助我們比較不同景氣區間之差異,然而股票市場之複雜、非線性及不可預測性也經常成為各統計資料失準的關鍵,因此,本篇論文以複雜網路作為分析股票市場之模型,並將各個股票表示成節點、股價變化之關聯性作為連結下,建立出複雜網路,藉此探討股市中的景氣差異。   在本研究中,先利用國發會制定的景氣對策信號,來幫助我們選取四段景氣區間,接著將台積電作為網路核心建構個股的相關網路。並以最小生成樹(Minimum Spanning Tree) 將複雜的股票網路簡單化。同時我們計算出各股相關網路之全域網路參數(Global Network Parameters)及區域網路參數(Regional Network Parameters),以利我們討論兩段景氣好區間與兩段景氣差區間之差異。最後,我們將股市相關網路以分層樹(Hierarchical Tree)來表示,以了解網路分群的結果。   結果顯示,我們建構的個股相關網路符合小世界網路特性,在全域網路參數中,景氣好相關網路之常規化平均特徵路徑(Normalization Average Characteristic Path Length)及景氣差相關網路中之平均群聚係數(Average Clustering Coefficient)、平均特徵路徑(Average Characteristic Path Length)、常規化平均特徵路徑(Normalization Average Characteristic Path Length)有顯著差異。 在區域網路參數中,在景氣好相關網路中,被選為網路樞紐並有顯著差異之個股有台達化、宜進與華通,景氣差相關網路則有瑞利、日月光、矽品及萬企。在景氣好相關網路比較時,台積電的連結度與點效率皆具有顯著差異。
12

工商及服務業普查資料品質之研究 / Data quality research of industry and commerce census

邱詠翔 Unknown Date (has links)
資料品質的好壞會影響決策品質以及各種行動的執行成果,所以資料品質在近年來越來越受到重視。本研究包含了兩個資料庫,一個是產業創新調查資料庫,一個是95年工商及服務業普查資料庫,資料品質的好壞對一個資料庫來說也是一個相當重要的議題,資料庫中往往都含有錯誤的資料,錯誤的資料會導致分析結果出現偏差的狀況,所以在進行資料分析之前,資料清理與整理是必要的事前處理工作。 我們從母體資料分佈與樣本資料分佈得知,在清理與整理資料之前,平均創新員工人數為92.08,平均工商員工人數為135.54;在清理與整理資料之後,我們比較兩個資料庫員工人數的相關性、相似性、距離等性質,結果顯示兩個資料庫的資料一致性極高,平均創新員工人數與平均工商員工人數分別為39.01與42.12,跟母體平均員工人數7.05較為接近,也顯示出資料清理的重要性。 本研究使用的方法為事後分層抽樣,主要研究目的是要利用產業創新調查樣本來推估95年工商及服務業普查母體資料的準確性。產業創新調查樣本在推估母體從業員工人數與母體營業收入方面皆出現高估的狀況,推測出現高估的原因是產業創新調查母體為前中華徵信所出版的五千大企業名冊為母體底冊,而工商及服務業普查企業資料為一般企業母體底冊。因此,我們利用和產業創新調查樣本所相對應的工商普查樣本做驗證,發現95年工商及服務業普查樣本與產業創新調查樣本的資料一致性極高。 / Data quality is good or bad will affect the decision quality and achievements in the implementation of various actions, so the data quality more and more attention in recent years. This study consists of two databases, one is the industrial innovation survey database, another is the industry and commerce census database in ninety five years. Data quality is good or bad of a database is also a very important issue, the database often contain erroneous information, incorrect information will result in bias of the analysis results. So before carrying out data analysis, data cleaning and consolidation is necessary. We can know from the parent and the sample data distribution. Before data cleaning and consolidation, the average number of innovation employees is 92.08, and the average number of industrial-commerce employees is 135.54. After data cleaning and consolidation, we compare the correlation, similarity, and distance of the number of employees in two databases. The results show the data consistency of the two databases is very high, the average number of innovation employees is 39.01, and the average number of industrial-commerce employees is 42.12, it is closer to the average number of parent employees 7.05. This also shows the importance of data cleaning. Method used in the study is post-stratified sampling, the main research objective is to use industrial innovation survey sample to estimate the data accuracy of the industry and commerce census in ninety five years. Use industrial innovation survey sample to estimate the number of employees and operating revenue in the industry and commerce census in ninety five years are both overestimated, we guess the reason is that the parent of the industrial innovation survey is five thousand large enterprises published by China Credit Information, and the parent of the industry and commerce census is general enterprises. Therefore, we use the corresponding industry and commerce census sample for validation. The results show that the data consistency of the industrial innovation survey sample and the industry and commerce census sample in ninety five years is very high.

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