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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.
1

少子女化社會的人口依賴負擔-台灣未來勞動力的隨機推計

胡力中, Hu, Li Chung Unknown Date (has links)
近來少子女化及高齡化是相當受到矚目的人口發展趨勢。伴隨這兩種趨勢而來的現象是人口依賴負擔的增加及勞動力的減少。經建會每兩年針對未來台灣人口發展趨勢進行人口推計。然而,經建會的人口推計僅包含基本的人口訊息,並未包含未來可能勞動力的變化情形。同時,人口依賴負擔的測量亦是以代表人口結構的扶養比進行測量,並未納入勞動力人數變化這項經濟因素,因此較無法反應真實的人口負擔情形。故而,本研究以納入勞動力變遷情形的經濟依賴比來測量未來台灣的人口依賴負擔。 本研究以1978年至2007年人力資源調查資料,運用區塊拔靴法推估未來台灣勞參與率的變化趨勢,並結合人口推計,進行台灣未來勞動力的隨機推計。研究結果顯示,台灣中高年齡勞動力參與率的情形逐年下滑,再加上工作年齡人口的老化。勞動力人數負成長的時點將早於人口負成長,且減少的幅度大於人口負成長。此外,運用經濟依賴比測量所顯示的人口負擔情形,更是比扶養比所反應的更為嚴重。 面對這樣的衝擊,人口政策不單可以從提振生育水準及提高國際移民的方向來調整人口結構,以減緩人口負擔及勞動力減少的情形,更可以增加中高齡人口投入勞力市場的誘因,以減少勞動力人數下滑的幅度及人口負擔的加劇。 關鍵詞:人口負擔、區塊拔靴法、勞動力推計、經濟依賴比
2

用拔靴法建構無母數剖面資料監控之信賴帶 / Nonparametric profile monitoring via bootstrap percentile confidence bands

謝至芬 Unknown Date (has links)
近年來剖面資料的監控在統計製程控制中有很大範圍的應用。在這篇論文裡,我們針對監控無母數剖面資料提出一個實務上的操作方法。這個操作方法有下列這些重要的特色:(1)使用一個靈活且有計算效率的無母數模型B-spline來描述反應變數與解釋變數的關係;(2)一般迴歸模型中之殘差結構假設是不需要的;(3)允許剖面資料內之觀測值間具有相關性之結構。最後,我們利用一個無線偵測器的實際資料來評估所提出方法的效率。 / Profile monitoring has received increasingly attention in a wide range of applications in statistical process control (SPC). In this work, we propose a practical proposed guide which has the following important features: (i) a flexible and computationally efficient smoothing technique, called the B-spline, is employed to describe the relationship between the response variable and the explanatory variable(s); (ii) the usual structural assumptions on the residuals are not require; and (iii) the dependence structure for the within-profile observations is appropriately accommodated. Finally, a real data set from a wireless sensor is used to evaluate the efficiency of our proposed method.
3

小區域生育率與人口推計研究 / Small Population Projections:Modeling and Evaluation

曹郁欣, Eunice Y. Tsao Unknown Date (has links)
由於許多國家死亡率下降快速、壽命延長幅度超乎預期,加上生育率持續低於替代水準,人口老化現象愈發明顯,近年來個人生涯規劃及政府施政,都格外強調退休後經濟生活及老年相關社會資源分配的比重。以臺灣為例,行政院經濟建設委員會 (簡稱經建會) 從1990年代開始,每兩年公布一次未來的人口推估,但過去十年來經建會屢次修正歷年的推估假設,以因應生育率及死亡率變化快速,適時提醒臺灣日益加速的人口老化。正因為人口推估可能受到人口數、社會變遷、資料品質等因素,影響統計分析的可靠性,常用於國家層級的推估方法,往往無法直接套用至縣市及其以下的層級 (即小區域),使得小區域人口推估較為棘手,需要更加謹慎面對。 本文延續王信忠等人 (2012) 的研究,以小區域人口推估為目標,著重在生育率推估研究,結合隨機模型與修勻方法,尋找適合臺灣縣市層級的小區域人口推估方法。本文考量的隨機模型計有區塊拔靴法 (Block Bootstrap) 和 Lee-Carter 模型 (Lee and Carter 1992),以預測未來的生育率和死亡率,並套用年輪組成推計法 (或稱為人口要素合成法;Cohort Component Method) 及修勻 (Graduation) 方法,探討這些方法與人口規模之間的關係,評估用於小區域人口推估之可行性。 本文首先以電腦模擬,探討生育率的推估,討論是否可直接推估總生育率,類似增加樣本數的概念,取代各縣市的年齡別生育率,以取得較為穩定的推估。根據模擬結果,發現人口規模對出生數的推估沒有明顯的關係,只要使用總生育率、再結合區塊拔靴法,就足以提供穩定的推估結果。實證研究方面,以臺灣縣市層級的人口及其年齡結構 (例如:0-14歲、15-64歲、65歲以上) 為驗證對象,發現分析結果也與電腦模擬相似,發現以區塊拔靴法推估臺灣各縣市的總生育率、年齡組死亡率,其推估精確度不因人口規模而打折扣,顯示以區塊拔靴法推估總生育率、年齡組死亡率,可用於推估臺灣小地區的未來人口。 / Due to the rapid mortality reduction, prolonging human longevity is a common phenomenon and longevity risk receives more attention in 21st century. Many developed countries encounter many problems brought up by prolonging life, such as poor community infrastructure and insufficient financial pension funds for the elderly. Population Projection thus becomes essential in government planning in dealing with the population aging. However, rapid changes in mortality and fertility make the projection very tricky. It would be even more difficult to project areas with fewer populations (i.e., small areas) since it takes extra efforts to deal with the larger fluctuations in small population. The objective of the study is to construct a standard operating procedure (SOP) for small population projection. Unlike the previous study, e.g., Wang et al. (2012), we will take both the fertility and mortality into account (but set migration aside for simplicity). First, for the fertility projection, we evaluate if total fertility rates (TFR) are more appropriate than the age-specific fertility rates for small population. Also, we compare two fertility projection methods: Lee-Carter model and block bootstrap, and check which shows better results. Based on the computer simulation, we found that TFR performs better and the block bootstrap method is more sensitive to rapid fertility changes. As for mortality rate projection, we also recommend the standard operating procedure by Wang et al. (2012). However, the smoothing methods have limited impacts on mortality projection and can be ignored. In addition to simulation, we also apply the SOP for projecting the small population to Taiwan counties and it achieves satisfactory results. However, due to the availability of data, our method can only be used for short-term projection (at most 30 years) and these results might not apply to long-term projection. Also, similar to the previous work, the fertility rates have the larger impact on small population projection, although we think that the migration has large impact as well. In this study, only the stochastic projection is considered and we shall consider including expert opinions as the future study.
4

小區域人口遷徙推估研究 / A Study of Migration Projection for Small Area Population

黃亭綺, Huang Ting-Chi Unknown Date (has links)
國家政策之制定須配合未來人口總數及其結構等特性,藉以達到提高國民福 祉的願景,因此各國均定期公佈人口推估(Population Projection)的結果,目前臺 灣官方人口推估為每兩年公布一次。人口推估主要考量三個要素:出生、死亡、 遷移,以國家層級而言,通常遷徙對未來人口的影響遠小於出生與死亡,所以過 去行政院經濟建設委員會的官方全國人口推估一般專注於出生與死亡。然而,各 國研究發現遷徙是小區域人口推估為最重要的因素,人口數愈少、影響程度有愈 大的傾向,但文獻中較缺乏臺灣內部遷移的研究。如能掌握臺灣小區域人口遷徙 的變遷,將能使政策因地制宜,有助地方政府提高推行政策的有效性,也是本研 究之目標。 由於缺乏完整的縣市、鄉鎮市區層級的詳細遷移資料,本研究以人口平衡公 式反推淨遷移人數,找出各地區的遷移特性後,代入人口變動要素合成法(Cohort Component Method),搭配屬於機率推估的區塊拔靴法(Block Bootstrap),推估小 區域的未來人口。關於出生及死亡的推估,過去研究發現使用區塊拔靴法用於小 區域的生育率(曹育欣,2012)及死亡率(金碩,2011),皆有不錯的推估結果。 本研究以臺北市為範例,討論區塊拔靴法在小區域遷徙人口數、年齡別遷徙人口 的推估效果,及是否適合運用在其他不同縣市。 / The population projection is used to provide information for the policy planning of governments. In Taiwan, the Council for Economic Planning and Development is in charge of the official population projection and it release projection results every two years. Basically, three factors are considered in population projection: birth, death, and migration. Since the migration has little impacts in country-level projection, many countries (including Taiwan) assume the future migration is zero or close to zero, and the focus of projection is usually on the birth and death. However, for the projection of small area (such as county- or township-level), past studies found that the effect of migration cannot be ignored. But, partly due to the limitation of migration data, there are not many studies explore the migration patterns of counties or townships in Taiwan. In this study, we use the population records (births and deaths) and the population equation to derive the county-level records of internal migration in Taiwan. We use these data to explore the migration patterns of all counties in Taiwan, and then applying block bootstrap method to modify the county-level population projection. Note that, the block bootstrap is shown to be reliable in forecasting fertility (Tsao, 2012) and mortality (Jin, 2011) for small areas. In this study, we also use the Taipei City to demonstrate the population projection which includes the internal migration, and the result is promising.
5

過濾靴帶反覆抽樣與一般動差估計式 / Sieve Bootstrap Inference Based on GMM Estimators of Time Series Data

劉祝安, Liu, Chu-An Unknown Date (has links)
In this paper, we propose two types of sieve bootstrap, univariate and multivariate approach, for the generalized method of moments estimators of time series data. Compared with the nonparametric block bootstrap, the sieve bootstrap is in essence parametric, which helps fitting data better when researchers have prior information about the time series properties of the variables of interested. Our Monte Carlo experiments show that the performances of these two types of sieve bootstrap are comparable to the performance of the block bootstrap. Furthermore, unlike the block bootstrap, which is sensitive to the choice of block length, these two types of sieve bootstrap are less sensitive to the choice of lag length.

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