Iván Tamaredo holds a PhD in English studies from the University of Santiago de Compostela (Spain). His research interests include varieties of English, probabilistic variation, language processing, and linguistic complexity.

• List of abbreviations .......................................................................... 11 1 Introduction ................................................................................. 15 1.1 Communicative efficiency and language complexity .......... 15 1.2 Aims and research questions ............................................... 18 1.3 Structure of the book ........................................................... 21 2 Language complexity .................................................................. 25 2.1 Historical background ......................................................... 26 2.2 Sources of complexity variance ........................................... 31 2.2.1 Language contact ...................................................... 32 2.2.2 Acquisition versus use .............................................. 35 2.2.3 A typology of contact situations ............................... 38 2.2.4 Additional social determinants of complexity .......... 40 2.3 Measuring complexity ......................................................... 41 2.3.1 Kusters (2003, 2008) ................................................ 42 2.3.2 Miestamo (2006a, 2008) ........................................... 44 2.3.3 Hawkins (1994, 2004, 2009, 2014) .......................... 45 2.3.4 Comparison between the three metrics ..................... 48 2.3.5 Some important distinctions ..................................... 52 2.4 Complexity and varieties of English ................................... 55 3 Pronoun omission ........................................................................ 63 3.1 Generative approaches ......................................................... 65 3.2 Cognitive approaches .......................................................... 69 3.2.1 Agreement and context ............................................. 69 3.2.2 Accessibility theory .................................................. 73 3.2.3 Further factors .......................................................... 76 3.3 Pronoun omission in English ............................................... 79 3.3.1 Pronoun omission in the history of British English ..... 82 3.3.2 Constraints in Present-day English ........................... 84 3.4 The complexity and efficiency of pronoun omission .......... 904 A cross-varietal study of pronoun omission in English ............... 97 4.1 Simplification and substrate effects ................................... 100 4.2 Data and methodology ....................................................... 103 4.3 Results ............................................................................... 109 4.3.1 Global indexes: pronoun omission attestation and pervasiveness .......................................................... 109 4.3.2 Attestation and pervasiveness of individual features ................................................................... 117 4.4 Simplification and substrate effects revisited .................... 124 5 Complexity variance in English: pronoun omission and language contact ........................................................................ 129 5.1 Aims and purpose of the study .......................................... 130 5.2 Data and methodology ....................................................... 133 5.2.1 Corpus and data retrieval process ........................... 133 5.2.2 Varieties selected .................................................... 137 5.2.3 Variables included in the analysis ........................... 139 5.2.3.1 Language-external constraints ................... 140 5.2.3.2 Language-internal constraints ................... 141 5.2.3.3 Interim summary ....................................... 151 5.2.4 Statistical analysis .................................................. 152 5.2.4.1 Regression modelling and structural complexity ................................................. 153 5.2.4.2 Random forests and system complexity .... 155 5.3 Frequency of omitted and overt pronouns per variety ....... 157 5.3.1 Results .................................................................... 157 5.3.2 Discussion .............................................................. 170 5.4 Multivariate analysis of the data ........................................ 175 5.4.1 Structural complexity ............................................. 175 5.4.1.1 Results ....................................................... 175 5.4.1.2 Discussion ................................................. 190 5.4.2 System complexity ................................................. 193 5.4.2.1 Results ....................................................... 193 5.4.2.2 Discussion ................................................. 197 5.5 Complexity and contact revisited ...................................... 199 6 Concluding remarks and suggestions for further research ........ 203Appendix .......................................................................................... 213 List of figures ................................................................................... 247 List of tables ..................................................................................... 249 References and sources .................................................................... 253