Marginal Activity Access Cost (MAAC): a new indicator for sustainable Land Use/Transport (LUT) planning

The paper presents the ‘Marginal Activity Access Cost’, an accessibility indicator providing estimation in monetary terms of the impacts on mobility and on the environment of locating a single new activity in a specific zone of the urban area. In the first part of this paper, the new indicator is presented and compared to other accessibility indicators proposed in literature. In the second part, the MAAC is validated through an application to the urban area of Rome. The paper concludes with brief remarks on using the proposed accessibility indicator as index of performance for sustainable spatial planning.

Codeswitching in Igbo-English Bilingualism

This study evaluates the Matrix Language Frame model of codeswitching with Igbo-English data and concludes that the data can indeed be considered a classic case of codeswitching, in that a Matrix Language can be clearly identified in bilingual clauses. It establishes this through both qualitative and quantitative analyses that make use of the typological contrasts between Igbo and English to uncover supportive evidence for the Matrix Language Frame model and its associated three principles: the Matrix Language Principle, the Asymmetry Principle, and the Uniform Structure Principle. The investigation goes one step further by using spectrograms and the analysis of vowel harmony between English free morphemes and Igbo bound affixes to demonstrate that two phonologies can co-exist in codeswitching and that codeswitching forms are essentially pronounced with a phonology that does not entirely resemble that of the Matrix Language variety. Furthermore, the study finds that the same language production mechanisms as detailed under the Matrix Language Frame model and its associated three principles underlie both single word and multi-word codeswitching. That is, the present study, like those before it adopting the Matrix Language framework (see Amuzu 2010: 277), underlines the importance of the assumptions underpinning the Matrix Language Principle: (1) that language production is modular; (2) that lexical structure is both complex and abstract; and (3) that languages in contact divide responsibilities in what they may contribute toward lexical structure during the production of mixed constituents. Moreover, the study finds that Igbo-English bilinguals can always sustain ready access to their mother tongue mental lexicon during online speech production and thus Igbo-English may duly be described as a ‘classic’ case of codeswitching.