Listing Strategy Research Articles

Abstract 11621: Impact of Data Reporting on Outcome Analyses of Intra-Aortic Balloon Pump versus Impella Devices in Bridging Adult Heart Transplant Patients

Introduction: There is a paucity of evidence to guide temporary mechanic circulatory support (tMCS) as bridge to heart transplant (HTx). Question: Can matching techniques reveal device-related effects on peri-HTx outcomes between IABP (Intra-Aortic Balloon Pump) and Impella? Methods: Using the UNOS registry, this retrospective study selected adult patients listed as status 2 on IABP or Impella (V5.0 or V5.5) from 10/2018 to 1/2023. We assessed demographic, medical, hemodynamic, and biochemical data. Primary outcome was failure of status 2 listing strategy (composite of waitlist mortality, escalation of tMCS, and deactivation or delisting due to medical instability). Propensity scores were calculated using logistic regression and matching with a k-nearest neighbors classifier. Results: 3505 IABP and 648 impella patients were identified based on missingness: (1) No missing data (n = 991, 23%), (2) missing hemodynamic data (n = 1606, 39%), (3) missing both hemodynamic and biochemical data(n = 1664, 40%), and (4) the completedataset (n = 4153). Prior to matching,, failure on status 2 occurred in 12.1% of all patients, 11% of IABP patients, and 17.7% of impella patients in group 4 (p < 0.01). After matching, only in group 4 did impella patients have a significantly higher rate of failure on status 2 (12.6 vs 18%, p < 0.01). Average treatment effect for impella on failure of status 2 was nonsignificant for group 1(ATE 0.06, 95%CI -0.016-0.166) and significant for group 2(ATE 0.06; 95% 0.001-0.125), group 3 (ATE 0.05, 95%CI 0.012-0.094), and group 4 (ATE 0.067, 95%CI 0.037-0.102) cohorts, favoring IABP. There was an increase in request for status 2 by exception in group 4 for impella patients (9.8% vs 8.6%, p=0.04). Conclusion: IABP versus Impella had minimal to no impact on failure on status 2 for matched cohorts. Differences appeared when either biochemical or hemodynamic data were omitted. Complete data availability is crucial for developing trustworthy and actionable models.

Comparison of Evaluations for Heart Transplant Before Durable Left Ventricular Assist Device and Subsequent Receipt of Transplant at Transplant vs Nontransplant Centers

In 2020, the Centers for Medicare & Medicaid Services revised its national coverage determination, removing the requirement to obtain review from a Medicare-approved heart transplant center to implant a durable left ventricular assist device (LVAD) for bridge-to-transplant (BTT) intent at an LVAD-only center. The association between center-level transplant availability and access to heart transplant, the gold-standard therapy for advanced heart failure (HF), is unknown. To investigate the association of center transplant availability with LVAD implant strategies and subsequent heart transplant following LVAD implant before the Centers for Medicare & Medicaid Services policy change. A retrospective cohort study of the Society of Thoracic Surgeons Intermacs multicenter US registry database was conducted from April 1, 2012, to June 30, 2020. The population included patients with HF receiving a primary durable LVAD. LVAD center transplant availability (LVAD/transplant vs LVAD only). The primary outcomes were implant strategy as BTT and subsequent transplant by 2 years. Covariates that might affect listing strategy and outcomes were included (eg, patient demographic characteristics, comorbidities) in multivariable models. Parameters for BTT listing were estimated using logistic regression with center-level random effects and for receipt of a transplant using a Cox proportional hazards regression model with death as a competing event. The sample included 22 221 LVAD recipients with a median age of 59.0 (IQR, 50.0-67.0) years, of whom 17 420 (78.4%) were male and 3156 (14.2%) received implants at LVAD-only centers. Receiving an LVAD at an LVAD/transplant center was associated with a 79% increased adjusted odds of BTT LVAD designation (odds ratio, 1.79; 95% CI, 1.35-2.38; P < .001). The 2-year transplant rate following LVAD implant was 25.6% at LVAD/transplant centers and 11.9% at LVAD-only centers. There was an associated 33% increased rate of transplant at LVAD/transplant centers compared with LVAD-only centers (adjusted hazard ratio, 1.33; 95% CI, 1.17-1.51) with a similar hazard for death at 2 years (adjusted hazard ratio, 0.99; 95% CI, 0.90-1.08). Receiving an LVAD at an LVAD-transplant center was associated with increased odds of BTT intent at implant and subsequent transplant receipt for patients at 2 years. The findings of this study suggest that Centers for Medicare & Medicaid Services policy change may have the unintended consequence of further increasing inequities in access to transplant among patients at LVAD-only centers.

P-Ride: A Shareability Prediction Based Framework in Ridesharing

Ridesharing services aim to reduce travel costs for users and optimize revenue for drivers and platforms by sharing available seats. Existing works can be roughly classified into two types, i.e., online-based and batch-based methods. The former mainly focuses on responding quickly to the requests, and the latter focuses on meticulously enumerating request combinations to improve service quality. However, online-based methods perform poorly in service quality due to the neglect of the sharing relationship between requests, while batch-based methods fail in terms of efficiency. To obtain better service quality more efficiently, we propose a shareability prediction-based framework P-Ride. Specifically, we first introduce the k-clique listing strategy in graph theory based on the shareability graph to reduce the infeasible request combinations. Moreover, we extend the shareability graph to the hypergraph structure to represent the higher-order shareable relationships among requests. Furthermore, we devise a shareability prediction model that supports the prediction of sharable relationships for request combinations of an arbitrary size, which helps further filtering of candidate request combinations with GPU devices acceleration. The extensive experimental results demonstrate the efficiency and effectiveness of our proposed P-Ride framework.

Inclusive ABO-Incompatible Listing for Pediatric Heart Transplantation Results in Comparable Post-Transplant Rejection-Free Survival

<h3>Purpose</h3> ABO-incompatible (ABOi) heart transplantation (HT) has increased organ availability for infants with end-stage heart failure. Prior studies show comparable survival for ABOi versus compatible (ABOc) HT. We aimed to evaluate post-HT donor specific antibody (DSA), rejection (cellular or antibody-mediated), and cardiac allograft vasculopathy (CAV) utilizing an inclusive listing strategy. Institutional practice is to list all infants (0-24 months) for ABOi HT, irrespective of isohemagglutinin titers. <h3>Methods</h3> All HT recipients listed at less than 24 months of age at our institution from 2010-2020 were included. Pre- and post-operative variables were compared for ABOi and ABOc recipients. Separate iso-IgG and iso-IgM titers were monitored pre-HT. Primary outcomes included: treated rejection, DSA, CAV, primary graft failure requiring mechanical circulatory support, re-HT, and mortality. <h3>Results</h3> 51 HTs were performed on 50 patients from 2010-2020 (ABOi, N=13; ABOc, N=38). Pre-operative variables were comparable between groups. Isohemagglutinin monitoring revealed peak pre-HT titer within the ABOi cohort of 1:256 and 1:128, for IgG and IgM respectively. Peak titers at HT were IgG 1:16 and IgM 1:64. Five patients had IgG titers higher than matched IgM titers; 3 had IgG lower than IgM. Six ABOi recipients received intra-operative plasma exchange for elevated titers. Treated rejection, DSA, CAV, primary graft failure, need for re-HT, and survival were no different between groups in mid-term follow-up (Figure). <h3>Conclusion</h3> An inclusive approach to ABOi HT listing for infants less that 24 months of age results in comparable post-transplant rejection-free survival, CAV, and prevalence of DSA. These data support ABOi listing, even with high titer antibodies. Our results also show differences between IgG and IgM titers, whereas most centers report only the total. Determining IgG versus IgM may result in a better understanding of immunologic risk at high titers.

Impact of heart transplant allocation change on competing waitlist outcomes among listing strategies.

In 2018, the United Network for Organ Sharing (UNOS) adopted a 6-tier system for heart allocation which shifted patterns in listing strategies. The effects of the change on waitlist survival and transplantation rates have yet to be substantiated by analysis of competing outcomes among various listing strategies. This study included all adult patients listed for first-time heart transplantation in UNOS between 10/17/15 and 6/12/20. Clinical characteristics were compared before and after allocation change among various listing strategies: no support, inotropes, intra-aortic balloon pump, durable left ventricular assist device (LVAD), temporary VAD, and extracorporeal membrane oxygenation. Fine-Gray proportional subhazard models were used to estimate the effect of allocation change on competing waitlist outcomes-transplantation, death, or removal from waitlist-among each strategy. During the study period, there were 17422 patients listed for heart transplantation. Among each listing strategy, clinical characteristics were similar before and after allocation change. Subhazard models demonstrated reduced risk for waitlist mortality (p<.001) among each strategy except temporary VAD and increased transplantation rates (p<.001) among each strategy except for durable LVAD. These results validate the association of the new allocation system on waitlist outcomes across listing strategies.

Purchasing alliances and product variety

We analyze the impact of purchasing alliances on product variety and profit sharing in a setting, in which capacity constrained retailers operate in separated markets and select their assortment in a set of differentiated products offered by heterogeneous suppliers (multinationals vs. local SMEs). Retailers may either have independent listing strategies or build a buying group, thereby committing to a joint listing strategy. This alliance may cover the whole product line (full buying group) or only the products of large suppliers (partial buying group). We show that a buying group may enhance the retailers’ buyer power and reduce the overall product variety to the detriment of consumers. Our most striking result is that partial buying groups do not protect the small suppliers from being excluded or from bearing profit losses; they may even be more profitable for retailers than full buying groups.

Management of Active Surveillance-Eligible Prostate Cancer during Pretransplantation Workup of Patients with Kidney Failure: A Simulation Study.

The general rule that every active malignancy is an absolute contraindication for kidney transplantation is challenged by kidney failure patients diagnosed with active surveillance-eligible prostate cancer during pretransplantation workup. Interdisciplinary treatment teams therefore often face the challenge of balancing the benefits of early kidney transplantation and the risk of metastatic progression. Hence, we compared the quality-adjusted life expectancy of different management strategies in kidney failure patients diagnosed with active surveillance-eligible prostate cancer during pretransplantation workup. A discrete event simulation model was developed on the basis of a systematic literature search, clinical guidelines, and expert opinion. After model validation and calibration, we simulated four management strategies in a hypothetical cohort of 100,000 patients: Definitive treatment (surgery or radiation therapy) and listing after a waiting period of 2 years, definitive treatment and immediate listing, active surveillance and listing after a waiting period of 2 years, and active surveillance and immediate listing. Individual patient results (quality-adjusted life years; QALYs) were aggregated into strategy-specific means (± SEs). Active surveillance and immediate listing yielded the highest amount of quality-adjusted life expectancy (6.97 ± 0.01 QALYs) followed by definitive treatment and immediate listing (6.75 ± 0.01 QALYs). These two strategies involving immediate listing not only outperformed those incorporating a waiting period of 2 years (definitive treatment: 6.32 ± 0.01 QALYs; active surveillance: 6.59 ± 0.01 QALYs) but also yielded a higher proportion of successfully performed transplantations (72% and 74% versus 56% and 59%), with less time on hemodialysis on average (4.02 and 3.81 years versus 4.80 and 4.65 years). Among kidney failure patients diagnosed with active surveillance-eligible prostate cancer during pretransplantation workup, the active surveillance and immediate listing strategy outperformed the alternative management strategies from a quality of life expectancy perspective, followed by definitive treatment and immediate listing.

Value-Based Pricing Alternatives for Personalised Drugs: Implications of Asymmetric Information and Competition.

The market for new drugs is changing: personalised drugs will increase the heterogeneity in patients' responses and, possibly, costs. In this context, price regulation will play an increasingly important role. In this article, we argue that personalised medicine opens new scenarios in the relationship between value-based prices, regulation and industry listing strategies. Our focus is on the role of asymmetry of information and competition. We show that, if the firm has more information than the payer on the heterogeneity in patients' responses and it adopts a profit-maximising listing strategy, the outcome may be independent of the choice of the type of value-based price. In this case, the information advantage that the manufacturer has prevents the payer from using marginal value-based prices to extract part of the surplus. However, in a dynamic setting where competition by a new entrant is possible, the choice of the type of value-based price may matter. We suggest that more research should be devoted to the dynamic analysis of price regulation for personalised medicines.

Idioms: The type-sensitive storage model

Abstract Idiom surveys conducted on both English and Hebrew motivate a distinction between phrasal idioms, which are headed by a lexical head, and clausal idioms, which involve sentential functional material. The surveys show that these two types of idioms have different patterns of distribution across diathesis alternations. A verbal passive phrasal idiom necessarily shares its idiomatic meaning with the corresponding transitive, while the unaccusative, adjectival passive and transitive can head their own phrasal idioms. This behavior of phrasal idioms contrasts with the strong tendency of clausal idioms to be specific to a single diathesis. The Type-Sensitive Storage (TSS) model, which we propose, accounts for these findings, by motivating a different storage (lexical listing) strategy for each idiom-type. Phrasal idioms are argued to be stored as subentries, while clausal idioms are independent entries. Assuming the verbal passive is derived post-lexically, thus lacking its own lexical entry, the model explains why it cannot host idiomatic meanings specific to it. In contrast, the adjectival passive, unaccusative and transitive have their own lexical entries under the model, and thus can have their own idiomatic meanings. Clausal idioms are stored as independent entries, and therefore their storage does not depend on the existence of other lexical entries.

Procedure Preference and Intention-to-Treat Outcomes after Listing for Lung Transplantation among U.S. Adults. A Cohort Study.

Bilateral lung transplantation is widely used to treat chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD), on the basis of an expectation of improved survival after transplantation. Yet, waiting list mortality is higher while awaiting bilateral transplantation. The net effect of procedure preference on overall survival is unknown. To determine whether an unrestricted procedure preference is associated with improved overall outcomes after listing for lung transplantation. We performed a retrospective cohort study of 12,155 adults with COPD or ILD listed for lung transplantation in the United States between May 4, 2005, and December 31, 2014. We defined a "restricted" procedure preference as listing for "bilateral transplantation only" and an "unrestricted" procedure preference as listing for any combination of bilateral or single lung transplantation. We used a composite "intention-to-treat" primary outcome that included events both before and after transplantation, defined as the number of days between listing and death, removal from the list for clinical deterioration, or retransplantation. In adjusted analyses, an unrestricted procedure preference was associated with a 3% lower rate of the primary intention-to-treat outcome in COPD (adjusted hazard ratio [aHR], 0.97; 95% confidence interval [CI], 0.89-1.07) and a 1% higher rate in ILD (aHR, 1.01; 95% CI, 0.94-1.08). There was no convincing evidence that these associations varied by age, disease severity, or the use of mechanical support. Among those with ILD and concomitant severe pulmonary hypertension, an unrestricted preference was associated with a 17% increased rate of the primary outcome (aHR, 1.17; 95% CI, 0.99-1.39). An unrestricted preference was consistently associated with lower rates of death or removal from the list for clinical deterioration and with higher rates of transplantation. Graft failure rates were similar among those listed with restricted and unrestricted preferences. When considering outcomes both before and after transplantation, we found no evidence that patients with COPD or ILD benefit from listing for bilateral lung transplantation compared with listing for a more liberal procedure preference. An unrestricted listing strategy for suitable candidates may increase the number of transplants performed without impacting overall survival.

THE EFFECT OF PICTURE WORD INDUCTIVE MODEL (PWIM) AND STUDENTS’ SELF-EFFICACY TOWARD THEIR WRITING SKILL OF DESCRIPTIVE TEXTS AT GRADE X OF SMA NEGERI 1 IX KOTO SUNGAI LASI

This study was written to see the effect of picture strategy inductive model (PWIM) and student self-efficacy to their skills in writing descriptive text. This research is a quasi-experimental design with factorial design. This research data is taken from the result of student writing skill test and self-efficacy questionnaire. Then, the data were analyzed by using t-test and two-way Anova through Minitab 14 application. The results of this study indicate that PWIM strategy has a significant effect on students' writing skill when compared with listing strategy used by teachers in writing teaching. The result shows a t count of 1,900 which is larger than the t-table that is worth 1.684. Then, students with high self-efficacy taught with the PWIM strategy have a better ability to write descriptive text than students taught with a listing strategy, where t counts are 3.160 which is greater than t-tables of 1.812. However, students with low self-efficacy taught by the PWIM strategy do not have a better ability to write descriptive text than students taught by a listing strategy that t-counts 1.730 smaller than t-tables of 1.812 . Furthermore, from the results of the study also found that there is no interaction between teaching strategies with self-efficacy to the writing skills of students where F-count is 0.08 higher than the F-table is 2.58.

Survival Post Heart Transplant by Listing Strategy

Impending changes in heart allocation policy in the US may impact listing strategies. Percutaneous LVADs will have increased priority in the new system. We sought to compare heart transplant outcomes by listing strategy.

The seller's listing strategy in online auctions: Evidence from eBay

This paper studies the seller's online listing strategy and its consequences. By focusing on the fixed-price posting, buy-it-now auction and regular auction, we empirically investigate how the sellers choose the listing format and its associated strategic instruments to better understand their strategic behavior. An empirical model that addresses plausible concerns about sample selection bias and endogeneity is constructed to capture a seller's strategic behavior and examine how auction outcomes are related to this behavior. Based on the estimated model, we then conduct a counterfactual analysis. We find a tradeoff between the expected revenue and sale duration for the three listing formats.

P085 Lung re-transplant with repeated mismatch HLA antigens

Avoidance of previous donor mismatched HLA antigens is often considered for lung re-transplant due to concerns of potential HLA sensitization and memory responses. However, this approach may result in the exclusion of a large number of potential donors from consideration. Recently, we successfully performed a re-transplant with a history of multiple repeated mismatches. A 30+ year old male with a past medical history of cystic fibrosis underwent two previous bilateral lung transplants in August 2004 and in November 2010. Both allografts failed due to CLAD/BOS that developed after respiratory viral infections. The patient also subsequently developed detectable class I and II HLA antibodies with a cPRA > 88% in May 2016. Among these antibodies, strong anti-A1, B7 and DQ2 were first donor HLA specific. The second donor shared an A3-B18-DR4 haplotype with the first donor but not the recipient. No HLA antibodies specific to this A3-B18-DR4 haplotype antigens or to any other mismatched HLA antigens of the second donor were detected. A third lung transplant became urgently necessary in October 2016. Adding his previous donors’ mismatched HLA antigens to the unacceptable HLA list resulted in a cPRA > 96%. Therefore, a personalized listing strategy was developed based on discussions between the HLA lab and the transplant program. A deceased donor became available in November 2016. The virtual crossmatch revealed that the donor had no unacceptable HLA antigens based on HLA antibody detection. However, this donor carried the A3-B18-DR4 haplotype which was a repeated mismatch haplotype of the previous two donors. Based on a risk and benefit assessment, this donor was accepted as the source of lungs for the third transplant. The patient received 5 plasmapheresis sessions post-transplant to prevent antibody mediated rejection. Frequent post-transplant HLA antibody monitoring has not detected development of donor specific antibodies to the third donor and the new allograft functions well. Lung re-transplant can be performed with a cross of a repeated HLA mismatch provided that the recipient has no detectable HLA antibodies specific to the current donor. Our preliminary findings obtained from our study conducted on UNOS lung transplant data supports this conclusion. An assessment of risk and benefit of crossing the repeated mismatch HLA antigens should be done on a case-by-case basis.

THE OPTIMAL LISTING STRATEGIES IN ONLINE AUCTIONS

This article proposes a unified framework to completely characterize the seller's optimal listing strategy in the online auction as a function of her rate of time impatience. Specifically, the fixed‐price listing, the regular auction, and the buy‐it‐now (BIN) auction are each a solution of the seller's single optimization problem under different values of the rate of intertemporal discount: The perfectly patient seller adopts the regular auction, the sellers with a medium range of time impatience adopt the BIN auction, and the most impatient of sellers adopt the fixed‐price listing. Moreover, under mild conditions, the reverse price is inversely related to the value of the seller's discount factor, either within or across formats. This in turn implies that the posted price in the fixed‐price sale is greater than the reserve price of the BIN auction, followed by that of the regular auction. These predictions offer clear empirical implications.

Listing-Oriented Logistics Service Strategy: A New Choice for Large Transactional Online Shopping Websites

Behind the fast development of online shopping market in China, there are the risk of bankruptcy and development dilemma caused by huge loss. This paper suggests that they should take improving logistics service quality as short-term goal, and appearing on the stock market as middle-term goal. By transferring a part of capital from pricing strategy and promoting strategy to logistics department, the logistics service quality could be greatly improved though with little profit or even loss. This could attract customers, enlarge sales and market shares, and finally attracting venture capital fund and realizing listing strategy successfully. This strategy is based on the principle of systematic optimization and called listing oriented logistics service strategy. Finally, this paper analyzes the acceptance of this listing oriented logistics service strategy with TAM model for large-sized transactional shopping websites, it would be increased with the pressure of fierce market competition as well as increased customer needs.

Optimal Listing Strategy in Online Auctions

This paper proposes a unified framework to completely characterize the sellers' optimal listing strategy in the online auction as a function of their rates of time impatience. Specifically, the fixed-price listing, the regular auction, and the buy-it-now auction are each a solution of the seller's single optimization problem under different values of the rate of inter-temporal discount: the perfectly patient seller adopts the regular auction; the sellers with a medium range of time impatience adopt the buy-it-now auction; and the most impatient of sellers adopt the fixed-price listing. Moreover, in the regular and buy-it-now auctions, the optimal reserve price is inversely related to the seller's inter-temporal discount factor, either within or across listing types.This implies that the optimal reserve price for the buy-it-now auction is greater than that of the regular auction. These predictions offer clear empirical implications.

ESTUDO DE CASO: COMO DUAS CRIANÇAS PASSAM A COMPREENDER A COMBINATÓRIA A PARTIR DE INTERVENÇÕES?

No presente estudo de caso foram analisados os desempenhos de dois alunos do 5º ano do Ensino Fundamental ao trabalharem com problemas combinatórios. Foram realizados pré-teste, duas sessões de intervenção e pós-teste com a turma inteira, porém, para a análise atual foi feito o recorte dos desempenhos de Lucas e Marcos[1], buscando-se analisar de forma detalhada como essas duas crianças passaram a compreender os quatro tipos de problemas combinatórios (Produto Cartesiano, Arranjo, Permutação e Combinação). Observaram-se as contribuições das intervenções, as quais foram baseadas na listagem de possibilidades como estratégia e em mais três pilares considerados importantes para a compreensão da combinatória: o destaque para os invariantes dos problemas combinatórios, a sistematização das possibilidades e a generalização. A estratégia da listagem foi observada como importante para o ensino, após ter sido detectada em estudos de sondagem anteriores como caminho utilizado por alunos de diferentes níveis escolares. Os demais pilares (invariantes, sistematização e generalização), apesar de aparecerem com menor frequência nos estudos de sondagem, são entendidos como facilitadores da compreensão combinatória, por isso o destaque para os mesmos durante as intervenções. Os dois alunos investigados demonstraram melhor desempenho em termos quantitativos e qualitativos, com maior quantidade de acertos e melhor compreensão dos problemas após as intervenções. Eles passaram a se utilizar dos pilares trabalhados nas intervenções, o que demonstra que o caminho escolhido para o trabalho com a combinatória foi significativo para a aprendizagem. Palavras-chave: Raciocínio combinatório; Intervenções; Tipos de problemas combinatórios; Educação básica. Agências financiadoras: CNPq e FACEPE [1] Os nomes Lucas e Marcos são fictícios, colocados para preservar a identidade dos alunos.

The Seller's Listing Strategy in Online Auctions: Evidence from Ebay

The paper empirically studies why the sellers of identical commodities adopt different auction formats in the online auction, and the consequences thereof. We postulate that the sellers adopt different auction formats because of the differences in their experience and the number of items they have. We first use these two characteristics to endogeneize the seller's choice between three auction formats: fixed-price, buy-it-now (BIN), and pure auctions. We then estimate the differences in sales rate, transaction price, and sale duration between the three formats. We find that the fixed-price auction results in the highest transaction price and the lowest sale rate, while the pure auction is just the opposite, with the BIN auction falling in between. These results strongly suggest that there is a tradeoff between price and sale probability in adopting different formats of auctions.

Cross listing, corporate governance and corporate performance

PurposeThe purpose of this paper is to explore whether corporate governance is the intermediary between the cross listing strategy and corporate performance.Design/methodology/approachThe paper first reviews the studies on cross listing and corporate governance, and then constructs the theoretical model to express the relationship between cross listing, corporate governance, and corporate performance. Then, the paper takes the regression test and mediating effects test with the companies listed in Hong Kong as the sample.FindingsEmpirical studies found that corporate governance is the intermediary between the cross listing strategy and corporate performance. Meanwhile, the study verified that cross listing strategy does enhance corporate performance.Originality/valueThe finding will help Chinese corporations choose another way to be international and practise the strategy of cross listing.