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In Sweden, three principles prescribed by law compose the ethical platform aiming to ensure a fair distribution of healthcare resources. The goals of each of the three principles are to 1: ensure equal care, regardless of personal characteristics or social function; 2: give priority to patients of bad health; 3: base priority decisions on cost-effectiveness. The weights given to the last two principles yield different implications on which pharmaceuticals and medical procedures to subsidize and can be seen as an equity-efficiency trade-off. Knowledge of the Swedish public's views on this balance has been stated to be of large value to decision-makers, to be used as a basis for priority decisions. However, no such information exists to date. A large share of studies from other countries has moreover provided counter-intuitive estimates, possibly indicating a need for methodological development. In this thesis, I provide a suggestion on a discrete choice approach to quantify opinions on how to weight disease severity and cost-effectiveness in healthcare prioritization. In addition, I present a novel method to use the estimates to rank treatments. The design is furthermore tested in a pilot study, being the first to investigate this question in a Swedish setting. The results indicate that the population values both the amount and distribution of health created, favoring individuals suffering from severe conditions, which is seen as in line with a priori expectations. The thesis contributes to the literature aiming to quantify opinions on healthcare prioritization.

Background and Objectives: Understanding patient and public values and preferences is essential to healthcare and policy decision making. Discrete choice experiments (DCEs) are a common tool used to capture and quantify these preferences. Recent technological advances allow for a variety of approaches to create and analyze DCEs. However, there is no optimal DCE design, nor analysis method. Our objectives were to (i) survey DCE simulation studies to determine what design features affect statistical efficiency, and assess their reporting, (ii) further investigate these findings with a de novo simulation study, and (iii) explore the sensitivity of individuals’ preference of attributes to several methods of analysis. Methods: We conducted a systematic survey of simulation studies within the health literature, created a DCE simulation study of 3204 designs, and performed two empirical comparison studies. In one empirical comparison study, we determined addiction agency employees’ preferences on knowledge translation attributes using four models, and in the second, we determined elementary school children’s choice of bullying prevention programs using nine models. Results and Conclusions: In our evaluation of DCE designs, we identified six design features that impact the statistical efficiency of a DCE, several of which were further investigated in our simulation study. The reporting quality of these studies requires improvement to ensure that appropriate inferences can be made, and that they are reproducible. In our empirical comparison of statistical models to explore the sensitivity of individuals preferences of attributes, we found similar rankings in the relative importance measures of attributes’ mean part-worth utility estimates, which differed when using latent class models. Understanding the impact of design features on statistical efficiency are useful for designing optimal DCEs. Incorporating heterogeneity in the analysis of DCEs may be important to make appropriate inferences about individuals’ preferences of attributes within a population. / Thesis / Doctor of Philosophy (PhD) / This thesis focuses on the design and analysis of preference surveys, which are referred to as discrete choice experiments. These surveys are used to capture and quantify individuals’ preferences on various characteristics describing a product or service. They are applied in various health settings to better understand a population. For example, clinicians may want to further understand a patient population’s preferences in regards to multiple treatment alternatives. Currently, there is no optimal approach for designing or analyzing preference surveys. We investigated what factors help improve the design of a preference survey by exploring the literature and conducting our own simulation study. We also investigated how sensitive the results of a preference survey were based on the statistical model used. Overall, we found that (i) increasing the amount of information presented and reducing the number of variables to explore will maximize the statistical optimality of the survey; and (ii) analyzing the data with different statistical models will yield similar results in the ranking of individuals’ preferences of the variables explored.

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京都大学 / 新制・課程博士 / 博士(農学) / 甲第24681号 / 農博第2564号 / 新制||農||1100(附属図書館) / 学位論文||R5||N5462(農学部図書室) / 京都大学大学院農学研究科生物資源経済学専攻 / (主査)教授 栗山 浩一, 教授 浅見 淳之, 教授 伊藤 順一 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

This dissertation is concerned with decision making in retail operations management. Specifically, we focus on pricing, variety, and inventory decisions, which are at the interface of the marketing and operations functions of a retail firm. We consider two problems that relate to two major types of retail goods. First, we study joint pricing, variety, and inventory decisions for a set of substitutable" items that serve the same need for the consumer (commonly referred to as a "retailer's product line"). Second, we present a novel model of a selling strategy for "complementary" items that we refer to as ``convenience tying," and focus on analyzing the effect of this selling strategy on pricing and profitability. We also study inventory decisions under convenience tying and exogenous pricing. For a product line of substitutable items, the retailer's objective is to jointly determine the set of variants to include in her product line ("assortment"), together with their prices and inventory levels, so as to maximize her expected profit. We model the consumer choice process using a multinomial logit choice model and consider a newsvendor type inventory setting. We derive the structure of the optimal assortment for a special case where the non-ascending order of items in mean consumer valuation and the non-descending order of items in unit cost agree. For this special case, we find that an optimal assortment has a limited number of items with the largest values of the mean consumer valuation (equivalently, the items with the smallest values of the unit cost). For the general case, we propose a dominance rule that significantly reduces the number of different subsets to be considered when searching for an optimal assortment. We also present bounds on the optimal prices that can be obtained by solving single variable equations. Finally, we combine several observations from our analytical and numerical study to develop an efficient heuristic procedure, which is shown to perform well on many numerical tests. With the objective of gaining further insights into the structure of the retailer's optimal decisions, we study a special case of the product line problem with "similar items" having equal unit costs and identical reservation price distributions. We also assume that all items in a product line are sold at the same price. We focus on two situations: (i) the assortment size is exogenously fixed, while the retailer jointly determines the pricing and inventory levels of items in her product line; and (ii) the pricing is exogenously set, while the retailer jointly determines the assortment size and inventory levels. We also briefly discuss the joint pricing/variety/inventory problem where the pricing, assortment size, and inventory levels are all decision variables. In the first setting, we characterize the structure of the retailer's optimal pricing and inventory decisions. We then study the effect of limited inventory on the optimal pricing by comparing our results (in the ``risky case" with limited inventory) with the ``riskless case," which assumes infinite inventory levels. In addition, we gain insights on how the optimal price changes with product line variety as well as demand and cost parameters, and show that the behavior of the optimal price in the risky case can be quite different from that in the riskless case. In the second setting, we characterize the retailer's optimal assortment size considering the trade-off between sales revenue and inventory costs. Our stylized model allows us to obtain strong structural and monotonicity results. In particular, we find that the expected profit at optimal inventory levels is unimodal in the assortment size, which implies that the optimal assortment size is finite. By comparison to the riskless case, we find that this finite variety level is due to inventory costs. Finally, for the joint pricing/variety/inventory problem, we find that even when the retailer has control over the price, finite inventories still restrict the variety level. We also propose several bounds that can be useful in solving the joint problem. We then study a convenience tying strategy for two complementary items that we denote by "primary" and "secondary." The retailer sells the primary item in an appropriate department of her store. In addition, to stimulate demand, the secondary item is offered in two locations: its appropriate department and the primary item's department where it is displayed in very close proximity to the primary item. We analyze the profitability of this selling practice by comparing it to the traditional independent components strategy, where the two items are sold independently (each in its own department). We focus on understanding the effect of convenience tying on pricing. We also briefly discuss inventory considerations. First, assuming infinite inventory levels, we show that convenience tying decreases the price of the primary item and adjusts the price of the secondary item up or down depending on its popularity in the primary item's department. We also derive several structural and monotonicity properties of the optimal prices, and provide sufficient conditions for the profitability of convenience tying. Then, under exogenous pricing, we find that convenience tying is profitable only if it generates enough demand to cover the increase in inventory costs due to decentralizing the sales of the secondary item. / Ph. D.

Insufficient knowledge of residential preferences represents a major obstacle to achieving residential satisfaction and quality of life. This obstacle is even greater in the case of transit-oriented developments (TODs), as their success depends, in part, on the degree to which people's preferences are consistent with their residential environments. This study employed a visual choice experiment, which combines the benefits of visual preference surveys and discrete choice experiments, to elicit residential preference for TODs in Riyadh, Saudi Arabia, before the opening of its citywide public transportation system. Using a seemingly homogeneous sample of participants, the analysis incorporated three analytical methods to elicit residential preference: a multinomial logit model, a mixed logit model, and a latent class model. The results indicated the presence of preference heterogeneity and the emergence of four lifestyle classes that could explain and predict residential preference patterns. People with similar sociodemographic characteristics may have different lifestyles based on their choice behavior, marital status, and public transit attitudes. Additionally, the results showed a strong preference for low-density housing, even among those who favor living in a TOD; however, increasing density could be mitigated through the presence of other TOD attributes. The findings of this research point to the diversity of residential preferences and suggest that providing a variety of residential environments increases the likelihood that people will find their preferred environment. Additionally, planning efforts to convert all developments near transit, particularly in suburban locations, to TODs might be unsuitable in cities where public transportation has been introduced only recently. Instead, deferring TOD conversion efforts until public transportation and its use are mature may attract people to live near transit and encourage the gradual development of transit affinity in residents who may otherwise reject TOD living completely. Lastly, the successful application of a visual choice experiment in this research opens up a variety of potential analytical methods that are used commonly in other fields and have the potential to move visual preference research into the realm of robust empirical investigation. / Ph. D. / The work of urban planners, urban designers, architects, and policy makers centers on improving the built environment and increasing the quality of people’s lives. However, their work entails making decisions that are not always in tandem with people’s preferences (e.g., increasing housing density, proposing a mix of land uses in residential neighborhoods, introducing public transportation close to where people live and work, to name a few). Due to the uncertainty surrounding people’s acceptance of modifications of the built environment, especially when it entails introducing residential attributes for the first time, this dissertation focused on 1) assessing residential preference near public transportation nodes in Riyadh, Saudi Arabia before operation of the public transportation system, and 2) assessing the extent to which advanced analytical methods are capable of providing a better understanding of residential preference differences among a seemingly homogenous sample of participants. The work in this dissertation was motivated by the increasing use of manipulated images in choice tasks, where participants are presented with multiple images, each depicting a residential scenario, as bundles to choose from, and their choice patterns then recorded and analyzed. The results showed that among the relatively homogenous sample of participants that was recruited, four significant residential preference patterns have emerged, which could be used to describe and predict residential preference and choice with great accuracy. This dissertation laid out several policy implications that could be useful in providing a built environment that matches with what people want. It also provided research implications and suggestions on the use of visual choice experiments for urban planners and designers that are well-developed in other fields of inquiry.

Yes / Background Recently, primary care in the United Kingdom has undergone substantial changes in skill mix. Non-medical prescribing was introduced to improve patient access to medicines, make better use of different health practitioners’ skills and increase patient choice. There is little evidence about value-based patient preferences for ‘prescribing nurse’ in a general practice setting. Objective To quantify value-based patient preferences for the profession of prescriber and other factors that influence choice of consultation for managing a minor illness. Design Discrete choice experiment patient survey. Setting and participants Five general practices in England with non-medical prescribing services, questionnaires completed by 451 patients. Main outcome measure Stated choice of consultation. Main results There was a strong general preference for consulting ‘own doctor’ for minor illness. However, a consultation with a nurse prescriber with positive patient-focused attributes can be more acceptable to patients than a consultation provided by a doctor. Attributes ‘professional’s attention to patients’ views’ and extent of ‘help offered’ were pivotal. Past experience influenced preference. Discussion and conclusion Respondents demonstrated valid preferences. Preferences for consulting a doctor remained strong, but many were happy to consult with a nurse if other aspects of the consultation were improved. Findings show who to consult is not the only valued factor in choice of consultation for minor illness. The ‘prescribing nurse’ role has potential to offer consultation styles that patients value. Within the study’s limitations, these findings can inform delivery of primary care to enhance patient experience and substitute appropriate nurse prescribing consultations for medical prescribing consultations. / Department of Health, Project 016/0108. NIHR, CDF/01/2008/009.

Die vier Beiträge der vorliegenden Dissertationsschrift untersuchen das Entscheidungsverhalten von Landwirten in unterschiedlichen Entscheidungssituationen. Das übergeordnete Ziel ist es, die Präferenzstruktur und Zahlungsbereitschaft von Landwirten in den untersuchten Entscheidungssituationen zu analysieren, um so die Informationsgrundlage als Entscheidungsbasis für Politiker und Berater sowie der Landwirte selbst zu erweitern. Hierzu findet die Methode der Discrete Choice Experimente in allen vier Beiträgen Anwendung. Im Einzelnen werden in den Beiträgen folgende Forschungsfragen untersucht: Der erste Beitrag prüft welche Faktoren die Entscheidung von Landwirten beeinflussen, den Preis für ihr Erntegut ex ante abzusichern. Im zweiten Beitrag werden die Präferenzen von Landwirten für das Eingehen einer Kooperation unter expliziter Berücksichtigung von nicht-monetären Faktoren analysiert. Der dritte Beitrag geht der Frage nach, welche Rolle die finanzielle Flexibilität in Investitionsentscheidungen von Landwirten spielt. Wie Anbauverträge für Biogas-Zuckerrüben aus Sicht der anbauenden Landwirte ausgestaltet sein müssen, wird im vierten Beitrag geklärt.

Bus is the main mode of urban transport in most cities in developing countries. Despite a high mode share, bus service quality is often poor and para-transit services are regarded as a problem in urban transport systems rather than a solution. Using Dhaka as a case study, this thesis investigates bus service quality through identification and valuation of thirteen important attributes using discrete choice models. The attributes examined are travel time, travel cost, waiting time, headway, priority seats for women, crowding inside the bus, boarding and alighting, picking up and dropping off passengers, bus stop facilities, driving quality, driver and crew behaviour, cleanliness inside the bus, and air conditioning. Five focus groups were conducted to identify key qualitative bus attributes and their levels in order to design choice experiments for valuation. A survey of 431 respondents in Dhaka was then undertaken. Two choice experiments were designed and implemented within the survey, each with seven attributes (set A and set B) with travel cost as the common attribute. Multinomial Logit (MNL) models and Mixed Logit (MXL) models were developed using the Dhaka choice data. Twelve of the thirteen attributes were statistically significant at the 99% level. The values of in-vehicle time (IVT), waiting time and headway were BDT 34.80, 47.40 and 64.20 per hour respectively for low income groups in the segmented model. Waiting time has a premium valuation, 1.36 times higher than IVT, which endorses existing evidence. The highest valuation is for the dummy variable seating all the way which is BDT 42.20 for high income females. The next largest was bus stops properly, picks and drops passengers nicely , followed by wide door and mild steps for boarding and alighting , smooth and safe journey , bus stop with shed, but no seating arrangements , and air conditioning . The lowest value was BDT 4.61 for deck and seats are clean and tidy , for the low income group. The WTP for the qualitative attributes is high, but given the poor level of the existing service and low fare levels this seems reasonable. Income has a significant impact on travel cost, as well as gender on priority seats for women and crowding inside the bus. However, household car ownership does not have a significant impact on any of the bus attributes examined. The high income group has 75% higher WTP for A set attributes and 79% higher WTP for B set attributes than low income group. Females have 76% higher WTP for standing comfortably all the way , but 38% higher WTP for seating all the way compared to the male. However, females have a WTP of BDT 0.44 for per percent of priority seats for women in contrast with males who have a WTP of BDT -0.11. There is significant taste heterogeneity for both quantitative and qualitative attributes. The qualitative attributes for picking up and dropping off passengers, boarding and alighting facilities and driving facilities have higher valuation and this attributes came from the existing within the market competition structure in a highly fragmented bus market. Therefore, it is recommended to introduce competition for the market and incentives for bus industry consolidation.