Consumer-generated reviews play an important role in online purchase decisions for many consumers. However, the quality and helpfulness of online reviews varies significantly. In addition, the helpfulness of different consumer-generated reviews is not disclosed to consumers unless they carefully analyze the overwhelming number of available contents. Therefore, it is of vital importance to develop predictive models that can evaluate online product reviews efficiently and then display the most useful reviews to consumers, in order to assist them in making purchase decisions. This thesis examines the problem of building computational models for predicting whether a consumer-generated review is helpful based on consumers' online votes on other reviews (where a consumer's vote on a review is either HELPFUL or UNHELPFUL), with the aim of suggesting the most suitable products and vendors to consumers.In particular, we propose in this thesis three different helpfulness prediction approaches for consumer-generated reviews. Our entropy-based approach is relatively simple and suitable for applications requiring simple recommendation engine with fully-voted reviews. However, our entropy-based approach, as well as the existing approaches, lack a general framework and are all limited to utilizing fully-voted reviews. We therefore present a probabilistic helpfulness prediction framework to overcome these limitations. To demonstrate the versatility and flexibility of this framework, we propose an EM-based model and a logistic regression-based model. We show that the EM-based model can utilize reviews voted by a very small number of voters as the training set, and the logistic regression-based model is suitable for real-time helpfulness predicting of consumer-generated reviews. To our best knowledge, this is the first framework for modeling review helpfulness and measuring the goodness of models. Although this thesis primarily considers the problem of review helpfulness prediction, the presented probabilistic methodologies are, in general, applicable for developing recommender systems that make recommendation based on other forms of user-generated contents.

The literature on price setting has developed extensively in the last decade; albeit predominantly focused on the price setting behaviour of developed countries. This study reviews the survey results of price setting behaviours in the manufacturing sector within a developing economy. More than two thirds of manufacturing firms in South Africa purely follow time-dependent pricing rules; which, when compared to the results of surveys conducted in other international studies is almost three times as much, approximately one third of firms allow for components of state-dependent pricing rules.Higher input costs (cost of raw materials and labour costs) are the most important driver behind price increases. Declining market share is the most important factor behind price reductions. Firms review their prices more often than they actually change them. The median firm in this study has only adjusted its prices twice in the last 12 months.Co-ordination failure and temporary shocks are the most important sources of price stickiness. Mark-up pricing and price discrimination are common practices amongst South African manufacturing firms. The quality of a firm‟s product followed by its price is most important in determining the firm‟s level of competitiveness. Manufacturing firms in South Africa generally adopt a barometric price leadership strategy when setting their prices. / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted

Thesis advisor: Michael Grubb / Online reviews have gained importance for consumers when shopping for experience goods. This dissertation documents the impact of Tripadvisor.com reviews on the hotel industry. In the first chapter, I investigate the causal impact of Tripadvisor review ratings on hotel performance via a regression discontinuity design. The results indicate that a 1-point increase in review rating leads to a 1.6% increase in revenue, a 1% increase in bookings, and a 0.4% to 0.6% increase in prices. Furthermore, the impact on bookings has increased over time. In the second chapter, I evaluate the welfare impact of Tripadvisor review ratings in providing information about quality. I develop a structural model of hotel demand and supply that takes price endogeneity and capacity constraints into consideration. Counterfactual experiments reveal that the removal of Tripadvisor from the status quo results in per-capita consumer surplus loss ranging from $0 to $5.8, with a more significant decrease in consumer surplus when prior knowledge about quality is less accurate. Hotels with higher quality than expected absent reviews benefit from review ratings, while the opposite is true for others. In the third chapter, I analyze the relative influence of Tripadvisor ratings on chain-affiliated and independent hotels and evaluate the value of Tripadvisor ratings compared to chain brands using the methodology developed in previous chapters. I find there is no significant difference in the effect of rating rounding on occupancy rates for chain-affiliated hotels versus independent hotels. Counterfactual experiment results suggest that despite chain brands providing value to consumers, Tripadvisor ratings provide additional value of about $0 to $4 per capita. In scenarios where Tripadvisor was not present, Chain-affiliated hotels benefit from brand affiliation while independent hotels are harmed. / Thesis (PhD) — Boston College, 2023. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Economics.

Background: Persistent anemia has been described in kidney transplant (KTx) recipients with parvovirus B19 virus infection. However, the epidemiology of parvovirus B19 and parvovirus B19-related anemia after KTx remains unclear. We conducted this systematic review (1) to investigate the incidence of parvovirus B19 infection after KTx and (2) to assess the incidence of parvovirus B19 among KTx patients with anemia. Materials and Methods: A systematic review was conducted in EMBASE, MEDLINE, and Cochrane databases from inception to March 2019 to identify studies that reported the incidence rate of parvovirus B19 infection and/or seroprevalence of parvovirus B19 in KTx recipients. Effect estimates from the individual studies were extracted and combined using random-effects, generic inverse variance method of DerSimonian and Laird. The protocol for this systematic review is registered with PROSPERO (no. CRD42019125716). Results: Nineteen observational studies with a total of 2108 KTx patients were enrolled. Overall, the pooled estimated seroprevalence of parvovirus B19 immunoglobulin G was 62.2% (95% confidence interval [CI]: 45.8%-76.1%). The pooled estimated incidence rate of positive parvovirus B19 DNA in the 1st year after KTx was 10.3% (95% CI: 5.5%-18.4%). After sensitivity analysis excluded a study that solely included KTx patients with anemia, the pooled estimated incidence rate of positive parvovirus B19 DNA after KTx was 7.6% (95% CI: 3.7%-15.0%). Among KTx with anemia, the pooled estimated incidence rate of positive parvovirus B19 DNA was 27.4% (95% CI: 16.6%-41.7%). Meta-regression analysis demonstrated no significant correlations between the year of study and the incidence rate of positive parvovirus B19 DNA (P = 0.33). Egger's regression asymmetry test was performed and demonstrated no publication bias in all analyses. Conclusion: The overall estimated incidence of positive parvovirus B19 DNA after KTX is 10.3%. Among KTx with anemia, the incidence rate of positive parvovirus B19 DNA is 27.4%. The incidence of positive parvovirus B19 DNA does not seem to decrease overtime.

No description available.

No description available.

Online reviews, which are consumer-generated messages, play a vital role in the consumer decision making process especially prior to their purchase adoption (i.e., pre-usage). The objective of this research is to investigate the effects of two-sided online reviews’ contents affecting the consumers' attitudes at the pre-usage stage of a focal experience service. Contrary to one-sided reviews (i.e., only positive or negative information), two-sided reviews contain both positive and negative information about a product/service: Two-sided reviews are considered more informative. Extant studies make an important assumption that there is no information asymmetry between writer/source of two-sided reviews and consumers that read/receive it. Their implicit assumption is that the attitude of the writer/source of the two-sided review is completely transferred to the reader/receiver of the review. Given the subjective nature of two-sided online reviews for experience goods, we contend that such an assumption is flawed because transfer of personal experience in form of attitude towards a focal object/service to others is fraught with ambiguity and uncertainty that can mitigate the transfer. Drawing on ambivalence and prospect theories, our hypothesis states that: the anticipatory ambivalence of the receiver/reader based on a two-sided review content for a focal service is higher than the ambivalent attitude of the source/writer of the review who has already experienced the focal service. Our empirical study, consisting of 1492 subjects from Canada and the United States, supports our stated hypothesis. The implication of our finding is profound. It shows that the extant literature had underestimated the negative attitude of the receiver/reader of the online reviews in their investigation, which confound their findings. To that end, we provide future research direction and implications of our findings in practice. / Thesis / Doctor of Philosophy (PhD)

No description available.

No description available.

Through four essays, this dissertation contributes to the body of marketing literature by advancing understanding of consumer interactions with digital decision aids. Different aspects of the content contained within digital decision aids are explored in several contexts. First, the drivers of consumer interactivity in an online review community are examined and it is found that violations of community norms are an important factor in stimulating consumer action. Second, a tool is developed to facilitate the normalization of online review content across languages. Next, elements of language and national culture are investigated to determine their influence on consumer reviews in an international context. It is found that cultural biases play an important role in the relative verbosity, valence, and helpfulness of online reviews across countries. Lastly, the role of images in digital decision aids is considered and it is found that image type and perspective can influence consumer product evaluation. In sum, the influence that content and context have on consumer interactions with digital decision aids is clearly demonstrated through a diverse yet intertwined set of studies. / Business Administration/Marketing