abstract: Bicycle sharing systems (BSS) operate on five continents, and they change quickly with technological innovations. The newest “dockless” systems eliminate both docks and stations, and have become popular in China since their launch in 2016. The rapid increase in dockless system use has exposed its drawbacks. Without the order imposed by docks and stations, bike parking has become problematic. In the areas of densest use, the central business districts of large cities, dockless systems have resulted in chaotic piling of bikes and need for frequent rebalancing of bikes to other locations. In low-density zones, on the other hand, it may be difficult for customers to find a bike, and bikes may go unused for long periods. Using big data from the Mobike BSS in Beijing, I analyzed the relationship between building density and the efficiency of dockless BSS. Density is negatively correlated with bicycle idle time, and positively correlated with rebalancing. Understanding the effects of density on BSS efficiency can help BSS operators and municipalities improve the operating efficiency of BSS, increase regional cycling volume, and solve the bicycle rebalancing problem in dockless systems. It can also be useful to cities considering what kind of BSS to adopt. / Dissertation/Thesis / Masters Thesis Urban and Environmental Planning 2018

住宅開發型態之決定，除考量住宅市場的需求外，尚需考量土地市場的供給。在臺北市單筆土地面積偏小之情況下，開發者若欲進行開發，整合土地之能力將成為影響開發規模之重要因素。然而，土地之產權型態、地主行為及偏好等因素，將影響開發者的整合成本。開發者往往因基地面積之限制而變更設計，甚或放棄開發。再者，影響住宅供給之重要因素除基地面積外，亦與開發強度息息相關。因此，在土地稀少、產權複雜或地價較高之地區，開發者應會增加單位土地的資本投入量以實現規模經濟。此外，在現行法規下，開發案若符合特定標準，即可申請政策性容積獎勵，使開發強度得以超過法定容積率之限制，進而影響最終之住宅開發型態與供給數量。為印證以上之推論，本研究以臺北市民國83年至104年第三種住宅區新建住宅之使用執造為基礎，建立開發個案之資料庫。先以敘述統計及地域型空間自相關分析開發型態，結果顯示：臺北市各行政區住宅開發型態各異，且產生空間聚集之情況。整體來看，市區主要為小基地、高容積之開發型態；而郊區開發量體較大，且偏向大基地、低容積之開發型態。 再者，本研究以多元線性迴歸模型探討影響基地面積與實際容積率之因素。實證結果顯示：影響住宅基地規模之關鍵為產權條件與整合因素，且市場中的確出現土地與資本替代的情形；而政策性容積獎勵增加了替代之彈性，亦可能降低土地整合之需要。此外，為了更深入了解產權條件與開發型態間之關聯，本研究進一步將臺北市十二個行政區劃分為原單筆土地面積較小之「產權複雜區」及原單筆土地面積較大之「產權單純區」，與實際開發案之土地筆數、面積及實際容積率進行交叉分析。結果指出：相對於產權單純之地區，產權複雜地區的開發土地面積較小，且開發者將更加強土地利用之強度，使建案呈現小基地、高容積之垂直發展型態。本研究之實證結果可以印證：產權複雜增加土地整合之成本，因此開發者需透過加強土地利用，增加經濟樓高，以達土地使用之規模經濟。而若欲擴大資本開發規模，與其進行成本較高之土地整合，開發者將傾向申請政策性容積獎勵。 / The pattern of housing development is decided by the needs of the housing market, as well as the supply of land. The plots in Taipei are overall small in size. Thus for developers, land assembly is an important factor that affects the development scale. Property rights, landlord behavior and preferences will affect the cost of land assembly, and force the developers to change design or even give up development due to the constraint of building sites size. Furthermore, important factors of the housing supply not only include the size of building sites, but also the building density. In areas where the land supply is inelastic, land prices tend to be high or property rights are complex, developers will therefore need to increase the amount of capital investment per unit of land in order to achieve economies of scale. In addition, if development projects meet certain requirements, developers can apply for floor area bonus that enable the building density to exceed the original legal limit of the floor-to-site ratio, thereby affecting the development patterns and the amount of housing supply. To verify these arguments, this study established a database of housing projects based on residential usage licenses from 1994 to 2015, and then used descriptive statistics and local spatial autocorrelation statistics to analyze housing development patterns. Results showed that development patterns varied from district to district and presented spatial clustering. On the whole, the site size was small and the building density was high in downtown area. In contrast the site size in the suburbs was relatively big, the building density was comparatively low and the amount of development was large. Furthermore, this study used regression models to explore factors affecting the size of building sites and the building density. The results showed that the key factors affecting the size of building sites were property rights and land assembly. Moreover, substitution between land and capital does occur. Nevertheless, floor area bonus increased the elasticity of substitution, and sometimes also reduced the incentive for land assembly. In order to better understand the correlation between property rights and development patterns, this study divided the twelve administrative districts of Taipei into "complex property areas" where individual plots were small, and "simple property areas" where individual plots were big, then analyzed the site size, number of land parcels and building density. The results pointed out that compared with the "simple property area", the site size was relatively small in the "complex property area", and developers would raise the intensity of land use. In consequence, buildings in "complex property area" tended to be on small sites with high density. The empirical results of this study suggested that complex property rights increased the cost of land assembly, and that led developers to increase the building density in order to achieve economies of scale of land use. However, if developers wish to create more floor areas, they tended to apply for floor area bonus rather than choose the costly land assembly.