Search Marsden awards 2008–2017

Recipient(s): Prof SE Stillman | PI | University of Otago
Dr RB Fabling | AI | Motu Economic and Public Policy Research
Prof JK Gibson | AI | University of Waikato

Public Summary: Wage differences for workers in different demographic groups, firms and locations have been documented in many empirical studies. For example, women in New Zealand earn, on average, 10-15 percent less than comparable men, while workers in the biggest firms earn 20 percent more than similar workers in the smallest firms. Understanding the cause of these so called ‘wage gaps’ is critical for evaluating the role of public policy in creating an equal playing field for different workers. However, previous research has not been able to account for possible differences in productivity that might instead explain these wages gap. Our proposed research will test competing hypotheses about three important wage gaps; the gender pay gap, the big firm wage premium and geographic wage differences, by exploiting unique longitudinal data collected by Statistics New Zealand on all employee-employer relationships in New Zealand. This data can be used to simultaneously measure wage and productivity differences across groups of workers and will allow us to use two methods to estimate the proportion of each observed wage gap that is explained by differences in worker productivity and evaluate possible explanations for any unexplained wage differences.

Recipient(s): Dr ZJ Weber | PI | University of Otago

Public Summary: Logical paradoxes have beset our best philosophical theories for millennia. Philosophical logic in New Zealand is emerging internationally for innovative responses to these problems. However, the very existence of seemingly unsolvable rational dilemmas remains completely unexplained. This project will give a new description of logical paradoxes, explaining them through mathematical models based on non-classical logics. The hypothesis is that paradoxes are conceptual boundaries, as shown in an intuitive geometric way by a formal theory of connected parts (mereotopology). The goal is to advance on the very idea of paradox, newly rendered in precise terms that facilitate philosophical progress.

Recipient(s): Prof GJ Martin | PI | Massey University

Public Summary: This proposal sits at the forefront of two central areas of modern mathematics; nonlinear analysis and low dimensional topology & geometry; unified by themes in conformal geometry and geometric function theory.

We attack important longstanding problems with wide ranging applications. These include the classification of conformal dynamical systems on manifolds and their dynamically defined invariants. This project interacts with our novel results in geometric group theory. We investigate the structure and classification of arithmetic hyperbolic orbifolds extending our solution of Sigel’s1945 problem by developing new methods to attack key problems in hyperbolic geometry.

We develop fundamentally new models in nonlinear materials science for the study of the failure of materials through stretching and tearing. These have medical applications through the deformation of cellular structures and thereby modeling heart form and function. Preliminary work has been validated and is now extended as part of this project.

This latter research is partly informed through and underpinned by our recent advances in geometric function theory and surprising connections with harmonic maps in general metrics (suggesting new approaches to the Schoen conjecture) and other novel techniques developed by us to study Nitsche type phenomena.

Recipient(s): Dr RC Macknight | PI | University of Otago
Dr J Weller | AI | University of Tasmania

Public Summary: Domestication by early farmers and improvement by modern breeders have dramatically transformed wild plants into today’s crops. Flowering time is a critical agronomic trait and its evolution was essential for the domestication and spread of wild plants into new climatic regions. This project aims to; (i) discover how legumes use seasonal changes in daylength and temperature to precisely control their flowering time and, (ii) understand how this process has evolved to allow natural populations of legumes to grow in new geographical regions. Ultimately, this knowledge will enable plant breeders to more efficiently develop new legume varieties tailored for different geographical regions.

Recipient(s): Dr FA Hodis | PI | Victoria University of Wellington
Prof JAC Hattie | AI | University of Melbourne

Public Summary: Students who lack motivation underachieve and miss important opportunities to acquire knowledge and skills. In no other educational settings is this problem more serious than at the secondary school level: students who fail to minimally achieve leave school without qualifications and, subsequently, have major difficulties continuing their education or finding sustainable employment. To overcome this important problem, it is essential to know what motivates students, whether motivation changes across the last years of secondary school, and how motivation and achievement relate to each other over time. Although extant research has taken important steps toward mapping motivated and unmotivated behaviours, these pivotal issues are far from being understood. The proposed research will overcome these fundamental limitations and provide answers to five salient questions: (a) What are the motivational orientations which, taken together, can describe accurately and efficiently student motivation? (b) How do these orientations work together to determine different types of motivation? (c) Do (some of) these motivational orientations change systematically across time? (d) For the motivational orientations that develop over time, are given change processes similar or different across observed (e.g., ethnicity, socioeconomic status) and unobserved groups? (e) How does change in motivation relate to change in achievement?

Recipient(s): Assoc Prof C Freeman | PI | University of Otago
Dr YM van Heezik | PI | University of Otago

Public Summary: That children need nature for health and well-being is widely accepted, but what type of nature?
The assumption that children must interact with wild pristine nature has been used to justify recognition of a 'nature deficit disorder', when such contact is lacking. However, recent research shows many urban areas support high biodiversity. Children may not suffer from a lack of connection with nature because they interact with nature in their neighbourhood, and even if social or cultural norms frustrate this access, there may still be sufficient diversity within their immediate nearby environment. We argue that the premise of an epidemic of 'nature deficit disorder' for children in western society is accepted uncritically and is adult-determined. By evaluating children's reported nature interactions and biodiversity within self-defined neighbourhood nature maps, we will explore nature contact from the child's perspective, emphasising nature in urban contexts. We will produce a child-centred biodiversity assessment, definition, and view of nature that will aid in better understanding the reality of children’s lived experiences and how children can be best supported to develop and maintain connections with the natural world.

Recipient(s): Dr MN McKubre-Jordens | PI | University of Canterbury
Dr Z Weber | AI | University of Otago

Public Summary: The original Calculus (Newton and Leibniz), and with it the theory of real numbers, was inconsistent. Although mathematicians have technically resolved this, deep conceptual mysteries surrounding the relationship of finite to infinite remain. Recent advances in logic - in particular, the development of paraconsistent logics - permit the coherent investigation of those aspects of structure that are otherwise hidden by inconsistency. A reasonable paraconsistent foundation for analysis of the real numbers remains conspicuously absent from the current state of human knowledge. The project addresses this knowledge gap.

This project will develop coherent models of the real numbers which classically are categorical with the usual real line, but distinguishable using a paraconsistent logic. On founding analysis paraconsistently, delicate questions arise concerning convergence of sequences, boundedness of sets, and continuity of functions, each of which are cornerstone notions necessary for an in-depth development of analysis. Surprising phenomena, such as increasing bounded sequences that do not converge, will emerge, with far-reaching implications for pure mathematics and theoretical computability. In tackling these questions, the project will lay the foundations for further significant developments in this prestigious subfield of mathematics.

Recipient(s): Dr TF Besier | PI | The University of Auckland
Prof DG Lloyd | AI | Griffith University
Dr TG McKay | AI | The University of Auckland

Public Summary: Movement disorders such as stroke, cerebral palsy and osteoarthritis dramatically impact quality of life. In walking, these disorders can alter muscle and joint forces leading to rapid joint degeneration. Movement retraining can be used to alter the mechanical loads placed on skeletal tissue and restore normal function. We seek to expand the scope and effectiveness of human movement retraining to make a real impact on quality of life. To achieve this, our novel system will integrate wearable sensors with computational models to estimate muscle and joint contact forces in real time and then provide intuitive tactile feedback using novel artificial muscle technology. We will test this movement retraining framework by altering the walking patterns of patients with knee joint osteoarthritis. This new approach to movement retraining has the potential to revolutionise rehabilitation strategies for a range of musculoskeletal disease and neuromuscular disorders.

Recipient(s): Dr MH Vickers | PI | The University of Auckland
Assoc Prof DM Sloboda | AI | McMaster University

Public Summary: What drives organisms to reproduce ? Is it different in males and females ? Is it regulated by the environment ? To date, we know little about environmental regulatory factors of reproductive function. In this proposal we aim to understand how fetal nutrition can change long-term reproductive strategy: that is, how these changes impact on pubertal onset and whether early puberty results in improved fertility and reproductive fitness. This study will begin to outline a novel mechanism by which nutritional influences modify reproductive maturation. Understanding how early life nutrition influences later life is vital for our understanding of human health, evolutionary biology and life history theory.

Recipient(s): Dr GM Anderson | PI | University of Otago
Prof DR Grattan | AI | University of Otago

Public Summary: Attenuation of anxiety during pregnancy and lactation in response to elevated levels of the hormone prolactin helps prevent programming of later-life diseases, and allows the mother to focus on nurturing dependent offspring. How this is achieved is unknown. The recently-discovered neuropeptide RFRP-3 is a potent stimulant of the stress axis, and during lactation prolactin acts on RFRP-3 neurons to suppress their output. We will use neuroanatomical techniques, combined with a new conditionally transgenic mouse line in which prolactin receptors are deleted specifically from RFRP-3 neurons, to characterise how these cells communicate the anxiolytic effects of prolactin to the stress axis.