The influence of fractal dimension and vegetation on the perceptions of streetscape quality in Taipei: with comparative comments made in relation to two British case studies

In this study we seek to determine the relationship between fractal dimension, the presence of vegetation, and pedestrian perception of streetscape in Taipei, Taiwan. We provide a fractal analysis of street vistas present in Taipei, calculate the amount of vegetation visible in the streets, and assess the perception of the visual quality characteristic of those streets. Correlations between the resultant fractal dimensions, the physical characteristics of the streets, and scores for a single measure of perceived visual quality are discussed and compared with the results from two similar British case studies. The key findings are that judgments of the visual quality of streetscapes are influenced by the presence of vegetation, but they are influenced more by changes in fractal dimension. Vegetation is shown have a strong, positive, and significant correlation with perceptions of variety, coherence, beauty, interest, and preference. Higher levels of vegetation were found in views that were judged as varied, coherent, beautiful, interesting, and likeable. The presence of visible sky and buildings in a view have negative correlations with judgments of variety and interest. The presence of visible boundaries, vehicles, signage, and street furniture all have strong positive correlations with judgments of complexity; conversely, they have strong negative correlations with judgments of order, coherence, and beauty. In the UK cases complexity was correlated positively with perceptions of visual quality, but in the Taiwanese case it was correlated negatively.