String order via Floquet interactions in atomic systems

We study the transverse-field Ising model with interactions that are modulated in time. In a rotating frame, the system is described by a time-independent Hamiltonian with many-body interactions, similar to the cluster Hamiltonians of measurement-based quantum computing. In one dimension, there is a three-body interaction, which leads to string order instead of conventional magnetic order. We show that the string order is robust to power-law interactions that decay with the cube of distance. In two and three dimensions, there are five- and seven-body interactions. We discuss adiabatic preparation of the ground state as well as experimental implementation with trapped ions, Rydberg atoms, and polar molecules.Comment: 8 pages, 6 figure

Tenant Mix Variety in Regional Shopping Centres: Some UK Empirical Analyses

The variety and quality of the tenant mix within a shopping centre is a key concern in shopping centre management. Tenant mix determines the extent of externalities between outlets in the centre, helps establish the image of the centre and, as a result, determines the attractiveness of the centre for consumers. This then translates into sales and rents. However, the management of tenant mix has largely been based on perceived “optimum” arrangements and industry rules of thumb. This paper attempts to model the impact of tenant mix on the rent paid by retailers in larger UK shopping centres and, hence, the returns made by shopping centre landlords. It extends work on shopping centre rent determination (see Working Paper 10/03) utilising a database of 148 regional shopping centres in the UK, with detailed data for over 1900 tenants. Econometric models test the relationship between rental levels and the levels of retail concentration and diversity, while controlling for a range of continuous and qualitative characteristics of each tenant, each retail product, and each shopping centre. Factor analysis is then used to extract the core retail and service categories from the tenant lists of the 148 shopping centres. The factor scores from these core retailer factors are then tested against rent payable. The results from the empirical analysis allow us to generate some clear analytical and empirical implications for optimal retail management.retail agglomeration, inter-store externalities, core-periphery model, shopping centre image

The Management of Positive Inter-Store Externalities in Shopping Centres: Some Empirical Evidence

In enclosed shopping centres, stores benefit from the positive externalities of other stores in the centre. Some stores provide greater benefits to their neighbours than others – for example anchor tenants and brand leading stores. In managing shopping centres, these positive externalities might be captured through rental variations. This paper explores the determinants of rent – including externalities – for UK regional shopping centres. Two linked databases were utilised in the research. One contains characteristics of 148 shopping centres; the other has some 1,930 individual tenant records including rent level. These data were analysed to provide information on the characteristics of centres and retailers that help determine rent. Factors influencing tenant rents include market potential factors derived from urban and regional economic theory and shopping centre characteristics identified in prior retail research. The model also includes variables that proxy for the interaction between tenants and the impact of positive in-centre externalities. We find that store size is significantly and negatively related to tenant with both anchor and other larger tenants, perhaps as a result of the positive effects generated by their presence, paying relatively lower rents while smaller stores, benefiting from the generation of demand, pay relatively higher rents. Brand leader tenants pay lower rents than other tenants within individual retail categories.shopping centres, retail location, externalities, rent levels

THE FEASIBILITY OF A BOXED BEEF FUTURES CONTRACT: HEDGING WHOLESALE BEEF CUTS

The purpose of this paper is to investigate the feasibility of a new futures contract for hedging wholesale transactions in the beef industry based on the USDA boxed beef cutout index (BBCO). The results suggest the live cattle futures contract is not an adequate tool to manage the price risk of wholesale meat transactions in the beef industry. However, a futures contract based on the BBCO index might provide considerably more opportunities for the hedging of wholesale meat cut prices. A pattern of improved hedging effectiveness at more distant horizons also appears to emerge for the individual cuts of meat using the conditional hedge procedures. These results may be of particular interest to members of the meat industry with longer planning horizons, and more diversified transactions.hedge ratio, hedging effectiveness, boxed-beef cutout, wholesale beef prices, Marketing,

Tree Dependent Identically Distributed Learning

We view a dataset of points or samples as having an underlying, yet unspecified, tree structure and exploit this assumption in learning problems. Such a tree structure assumption is equivalent to treating a dataset as being tree dependent identically distributed or tdid and preserves exchange-ability. This extends traditional iid assumptions on data since each datum can be sampled sequentially after being conditioned on a parent. Instead of hypothesizing a single best tree structure, we infer a richer Bayesian posterior distribution over tree structures from a given dataset. We compute this posterior over (directed or undirected) trees via the Laplacian of conditional distributions between pairs of input data points. This posterior distribution is efficiently normalized by the Laplacian's determinant and also facilitates novel maximum likelihood estimators, efficient expectations and other useful inference computations. In a classification setting, tdid assumptions yield a criterion that maximizes the determinant of a matrix of conditional distributions between pairs of input and output points. This leads to a novel classification algorithm we call the Maximum Determinant Machine. Unsupervised and supervised experiments are shown

An Exploratory Study Examining a Transformational Salesperson Model Mediated by Salesperson Theory-of-Mind

A customer revolution caused by the popularity of internet commerce, the reliance on social media, and the globalization of the retail industry, calls for an examination of a sales model driven by transformational salespeople. This study examined potential salesperson performance drivers and a proposed moderated mediation model of salesperson performance. This study relied upon a foundation of transformational and other leadership attributes and salesperson theory-of-mind (SToM). Although the conditional indirect effects of the model were not statistically significant, transformational leadership was found to be a statistically significant predictor of sales performance (c’=.024, t=2.63, p =.0088). Several sub-components of transformational leadership were also statistically significant such as individualized consideration (c’ = .133, t = 3.75, p = .0002). Other statistically significant leadership attribute predictors were contingent reward leadership (c’ = .102, t = 2.65, p = .0084), and laissez-faire leadership, negatively correlated, (c’ = -.061, t = -2.07, p = .039). The study also found that transformational leadership is positively related to SToM (ai = .768, t = 2.88, p = .0042). Although the study found these predictors statistically significant, caution must be exercised in the interpretation of results due to the low effect sizes. This study is suggestive for sales theory and for sales practice. The study contributes to the pioneering work of Bass (1997) who originally made the theoretical connection between transformational leadership attributes and effective sales performance. He theorized that because sales is an influence process involving the alignment of the customer’s goals and objectives with the organization’s solutions, it is like transformational leadership, which is also an influence process in which the leader responds to followers’ needs by aligning goals and objectives of individuals with the organization. The results not only confirm Bass’s theory, but also extend it with the addition of other leadership attributes, contingent reward leadership and laissez-faire leadership. This study employed a cross-sectional sampling approach and used data generated by an online package of surveys covering transformational leadership, salesperson theory-of-mind, and personality

AI – someone needs to know what’s going on!

When developing AI models, we must consider the cause and effect, whether the input-output relationship is meaningful, and is the relationship useful in predicting outcomes based on new data. This paper raises a crucial question about what a non-explainable vs explainable AI model means for the user and how a subject matter expert can play a critical role in AI model decision-making

AI – someone needs to know what’s going on!

When developing AI models, we must consider the cause and effect, whether the input-output relationship is meaningful, and is the relationship useful in predicting outcomes based on new data. This paper raises a crucial question about what a non-explainable vs explainable AI model means for the user and how a subject matter expert can play a critical role in AI model decision-making