Miracle-dz/UniFAR-FTUs huggingface dataset:
Bidding Strategies in Internet Yankee Auctions

In the past few years, we have witnessed a tremendous proliferation of transactions using the Internet as a virtual marketplace. U.S. News and World Report estimates the value of electronic commerce around $13 billion in 1998. In addition to transactions where prices are posted, sellers also use Internet auctions to sell goods such as clothing, collectibles, computers, and electronics. Current estimates place the value of auction transactions in the Internet at $30 million per week. A popular format for Internet auctions is the Yankee format. Here, a seller offers k identical units for sale, and bidders specify how many units they want and the per-unit price they want to pay. Bidding takes place progressively over a predetermined time period and the k highest bids at closing win the units at their specified prices. Ties are broken on the basis of quantities first and time of bidding second. Two features make these auctions different from standard auctions. First, unlike "live" auctions with fixed participation costs, entering each bid may be costly in a Yankee auction since bidding takes place over several hours (or days) and, in addition to connectivity cost, several minutes time must spend several registering the new price. Second, each time the bidder visits the auction site, she is uncertain about the competition since it is possible for more bidders to decide to enter before the closing. Here, we derive and characterize equilibrium strategies in simple Yankee auctions with stochastic demand. We show that costly bidding may induce bidders to bid high or jump bid in earlier rounds. These jump bids play a signaling role; they attempt to discourage later bidders from competing with established bidders. This way, under some conditions, both sender and receiver of the signal may be better off in equilibrium. The sender because deterring competition saves her the costs of additional bids, and the receiver because she avoids the costs of fruitless early competition. Here, we derive conditions on bidding costs and bidder types that result in a signaling equilibrium of this nature. We show that the characteristics of the equilibrium are closely related to the structure of demand uncertainty faced by the bidders since signal bidding has more strategic value when bidders anticipate further competition later in the auction. We use data from hundreds of Yankee Auctions to test some predictions of the jump-bidding model. In confirmation, we find (a) over 40% of the bidders in our sample enter jump bids, (b) any individual bidder is more likely to enter a jump bid as his first bid, (c) earlier bidders are more likely to enter jump bids than later bidders, (d) the relative size of a jump bid is increasing in the number of bidders relative to units being sold, and (e) the relative size of a jump bid is decreasing in the object's average value. We conclude with a discussion of the implications of costly bidding and jump-bidding strategies on Internet auction design.
Managing Risks: A New Framework

Risk management is too-often treated as a compliance issue that can be solved by drawing up lots of rules and making sure that all employees follow them. Many such rules, of course, are sensible and do reduce some risks that could severely damage a company. But rules-based risk management will not diminish either the likelihood or the impact of a disaster such as Deepwater Horizon, just as it did not prevent the failure of many financial institutions during the 2007–2008 credit crisis. In this article, Robert S. Kaplan and Anette Mikes present a categorization of risk that allows executives to understand the qualitative distinctions between the types of risks that organizations face. Preventable risks, arising from within the organization, are controllable and ought to be eliminated or avoided. Examples are the risks from employees’ and managers’ unauthorized, unethical, or inappropriate actions and the risks from breakdowns in routine operational processes. Strategy risks are those a company voluntarily assumes in order to generate superior returns from its strategy. External risks arise from events outside the company and are beyond its influence or control. Sources of these risks include natural and political disasters and major macroeconomic shifts. Risk events from any category can be fatal to a company’s strategy and even to its survival. Companies should tailor their risk management processes to these different risk categories. A rules-based approach is effective for managing preventable risks, whereas strategy risks require a fundamentally different approach based on open and explicit risk discussions. To anticipate and mitigate the impact of major external risks, companies can call on tools such as war-gaming and scenario analysis.
Propensity score analysis with partially observed confounders: how should multiple imputation be used?

Inverse probability of treatment weighting (IPTW) is a popular propensity score (PS)-based approach to estimate causal effects in observational studies at risk of confounding bias. A major issue when estimating the PS is the presence of partially observed covariates. Multiple imputation (MI) is a natural approach to handle missing data on covariates, but its use in the PS context raises three important questions: (i) should we apply Rubin's rules to the IPTW treatment effect estimates or to the PS estimates themselves? (ii) does the outcome have to be included in the imputation model? (iii) how should we estimate the variance of the IPTW estimator after MI? We performed a simulation study focusing on the effect of a binary treatment on a binary outcome with three confounders (two of them partially observed). We used MI with chained equations to create complete datasets and compared three ways of combining the results: combining treatment effect estimates (MIte); combining the PS across the imputed datasets (MIps); or combining the PS parameters and estimating the PS of the average covariates across the imputed datasets (MIpar). We also compared the performance of these methods to complete case (CC) analysis and the missingness pattern (MP) approach, a method which uses a different PS model for each pattern of missingness. We also studied empirically the consistency of these 3 MI estimators. Under a missing at random (MAR) mechanism, CC and MP analyses were biased in most cases when estimating the marginal treatment effect, whereas MI approaches had good performance in reducing bias as long as the outcome was included in the imputation model. However, only MIte was unbiased in all the studied scenarios and Rubin's rules provided good variance estimates for MIte.
Combination of thrombophilia markers in acute myocardial infarction of the young.

BACKGROUND The pathogenesis of arterial thrombotic disease involves multiple genetic and environmental factors related to atherosclerosis and thrombosis. But, there have been very few studies in India which have investigated some of the thrombophilia markers. AIM To look for combined thrombophilia in MI patients. SETTINGS AND DESIGN One hundred twenty patients of myocardial infarction (age below 40 yrs.) were recruited 8-10 weeks after stabilization. Hundred age and sex-matched healthy controls were also recruited in the present study. METHODS AND MATERIAL Following thrombophilia markers were screened in these patients--plasma fibrinogen, protein C, protein S, antithrombin III, factor V Leiden, PT G20210A polymorphism, MTHFR C677T, homocysteine, fibrinogen b448 Arg/Lys polymorphism and CBS T833C mutation. STATISTICAL ANALYSIS Statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 10.0, SPSS Inc., Chicago, USA. RESULTS AND CONCLUSION Elevated fibrinogen levels, homocysteine (p< 0.001 and homocysteine with odds ratio 6.26) and factor V Leiden (p=0.038) were independently associated with MI in our patients. A total of 37 patients (42.5%) had the presence of more than one thrombophilia markers in combination. Out of these, 10 had the presence of three markers in combination and 1 had five thrombophilia markers in combination. Only 2 controls had prothrombotic markers in combination. Combined prothrombotic risk factors were significant in cases in comparison to controls (p< 0.001). Further larger studies on a nationwide basis recruiting a large number of young MI patients should be done to substantiate these findings.
Variables affecting the real ear to coupler difference

The aim of this thesis was to compare real ear to coupler difference (RECD) values in different measurement configurations. To obtain fast predictions on the outcome of an RECD measurement, a plane wave transmission line model was made. Simulations of the effect of changes in different variables, makes it possible to investigate how these variables affect the RECD. These observations together with measurements in real ears and couplers can be used to explain how such variables affect the RECD. The model was validated by verification measurements in connection to a 2cc coupler, and an ear simulator, and proved its ability to accurately describe trends in RECD responses, where variables have changing parameters. Main findings include a comparison of three different hearing aid receivers connected to hearing aid hooks to represent the acoustics in undamped hearing aids with different receivers, and an Etymotic ER3A insert ear phone were made, and revealed substantial differences in RECD. Interactions between hearing aid tubing and receivers were also found to be significant, in the simulation study. The study concludes that the RECD response is affected by the entire acoustic system from the transducer to the medial end of the earmold’s sound bore. This knowledge is important to consider in the development of hearing aid fitting procedures and in regard to clinical practice. bl Moodie, Seewald & Sinclair (1994)Egolf & Leonard (1977)Egolf, Feth, Cooper & Franks (1985)Egolf, Haley, Howell & Larson (1988) Kjær (n.d.)Bentler & Pavlovic (1989)Feigin, Kopun, Stelmachowicz & Gorga (1989)Dillon (2001) Bagatto, Scollie, Seewald, Moodie & Hoover (2002)Saunders & Morgan (2003)Munro (2004)Hoover, Stelmachowicz & Lewis (2000)IEC (2006)Jacobsen (2006)Keefe (1984)Lampton (1978)Martin, Munro & Langer (1997)Munro & Buttfield (2005)Sinclair, Beauchaine, Moodie, Feigin, Seewald & Stelmachowicz (1996)Stinson & Lawton (1989)Warren (1999)Munro & Hatton (2000)Munro & Salisbury (2002)Munro & Toal (2005)Ricketts & Bentler (1995)Munro & Millward (2006)Gilman & Dirks (1986)Sanborn (1998)
Clinical and Bacterial Characteristics of Acute Bacterial Conjunctivitis in Children in the Antibiotic Resistance Era

Background: Acute conjunctivitis is the most common eye disorder in young children. Bacteria are responsible for 54–73% of all cases. The goals of the study were to identify the rates of Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis in cases of bacterial conjunctivitis in children and to define antibiotic resistance rates. Methods: During a 2-year study period, conjunctival swabs of children 2–36 months old were collected prospectively. Nontypable H. influenzae, S. pneumoniae and M. catarrhalis were defined as the study pathogens. Analyzed variables included demography, clinical presentation, bacteriologic results and susceptibility patterns. Results: There were 428 patients enrolled. Of all cultures, 55% (237 of 428) yielded at least 1 of the study pathogens. H. influenzae and S. pneumoniae were isolated from 29 and 20% of cultures, respectively. β-Lactamase production was found in 29% of H. influenzae isolates, and penicillin nonsusceptibility was observed in 60% of S. pneumoniae isolates. The most common S. pneumoniae serotypes were: 19F (14%); 6A and 14 (11% each). Nontypable S. pneumoniae was found in 12%. The 7-valent pneumococcal conjugate vaccine (PCV-7) could potentially cover 44% of all isolates. Conjunctivitis-otitis syndrome was found in 32% of patients, of whom 82% of cultures yielded H. influenzae. Conclusions: Antibiotic resistance rates are alarmingly high. Conjunctivitis-otitis syndrome, predominantly caused by H. influenzae, is quite common. The potential coverage of the PCV-7 in conjunctivitis is relatively lower than that reported in other pneumococcal infections. Our findings should alert physicians on the choice of appropriate antibiotic treatment, on the frequent copresence of acute otitis media and on the potential role of conjunctivitis in the spread of antibiotic-resistant pathogens.
The Impact of High Performance Work Systems in Irish Companies: An Examination of Company and Employee Outcomes

This study examines the impact of High Performance Work Systems (HPWS) on company and employee-level performance outcomes. At the company level, the study examines the outcomes of HPWS usage on innovation, productivity and turnover. The study uses data collected from 132 companies in Ireland who participated in a general manager (GM) and human resource (HR) manager survey conducted in 2006. This study shows that an extensive application of HPWS is associated with an increase in innovation, productivity and a reduction in voluntary turnover. At the employee level, the study examines employees’ perceptions of human resource management (HRM) practices and their impact on employee innovative work behaviour (IWB), organisational citizenship behaviour (OCB), and tenure intentions. Specifically, the study also measures whether employees’ perceptions of job demands mediate the relationship between employee perceptions of HRM practices and IWB, OCB and tenure intentions. Employee attitude surveys were conducted in five companies which took part in the General Manager/Human Resource Manager Survey in 2006. In total 220 employees were surveyed. In addition to employee surveys, interviews were carried out with HR managers or a relevant manager in the area of employee management in the five companies that participated at the employee level. Overall, employee-level findings suggest that positive employee perceptions of human resource management practices are associated with employee IWB, OCB and tenure intentions. Similarly, employee perceptions of human resource management practices have an indirect effect on employee outcomes, in particular IWB and organisational citizenship behaviour directed towards individuals (OCBI) via employee perceptions of job demands. This study uses cross-level inference (also known as the cross-level operator) to examine the impact of HPWS utilisation at company level on employee-level behavioural and attitudinal outcomes. Overall, cross-level findings suggest that greater use of HPWS is associated with positive employee perceptions of HRM practices and an increase in employee IWB, OCB and tenure intentions.
Enhancement of learning capacity and cholinergic synaptic function by carnitine in aging rats

The effects of a carnitine derivative, acetyl‐L‐carnitine (ALCAR), on the cognitive and cholinergic activities of aging rats were examined. Rats were given ALCAR (100 mg/kg) per os for 3 months and were subjected to the Hebb‐Williams tasks and a new maze task, AKON‐1, to assess their learning capacity. The learning capacity of the ALCAR‐treated group was superior to that of the control. Cholinergic activities were determined with synaptosomes isolated from the cortices. The high‐affinity choline uptake by synaptosomes, acetylcholine synthesis in synaptosomes, and acetylcholine release from synaptosomes on membrane depolarization were all enhanced in the ALCAR group. This study indicates that chronic administration of ALCAR increases cholinergic synaptic transmission and consequently enhances learning capacity as a cognitive function in aging rats. J. Neurosci. Res. 66:266–271, 2001. © 2001 Wiley‐Liss, Inc.
“A Prospective Randomized Case-Control Study To Evaluate Mini Right Thoracotomy versus Conventional Sternotomy For Mitral Valve Repair In Rheumatic Heart Disease.”

Purpose: Right mini thoracotomy has been evaluated in many studies for mitral valve repair mainly in degenerative valvular disease but not in rheumatic heart disease. Mitral valve repair is more challenging in rheumatic etiology due to complexity of lesions. This prospective randomized case control study was designed to evaluate repair through mini right thoracotomy and to compare the clinical and echocardiographic outcomes with sternotomy in rheumatic patients. Methods: 25 patients of rheumatic heart disease underwent mitral valve repair through mini right thoracotomy (group I). Various clinical and functional parameters were compared with 25 patients of mitral valve repair through sternotomy (group II). On follow up the results were compared in both groups for clinical and echocardiographic parameters. Results: The various pre-operative demographic parameters were comparable in two groups. Equal rate of mitral valve repair (group I-21/25, 84% and group II-21/25, 84%) was achieved in both groups. The various intra-operative and post-operative clinical parameters were better in group I . There were equivalent functional and valve related outcomes in both groups in term of NYHA class (1.28 ± 0.613 vs 1.08 ± 0.276, P = 0.144), post-operative mitral valve area (2.43 ± 0.891 vs 2.82 ± 0.662, P = 0.090), incidence of more than mild mitral regurgitation (0) and mean pressure gradient across mitral valve (4.98 ± 3.33 vs 4.23 ± 1.5, P = 0.309). Conclusion: Mitral valve repair through mini right thoracotomy approach in rheumatic etiology is feasible and safe with equivalent rate of successful repair as compared to median sternotomy. It is associated with lesser morbidity, cosmetic advantage and lesser resource utilization.
Recent Spread of a Retrotransposon in the Silene latifolia Genome, Apart From the Y Chromosome

Transposable elements often accumulate in nonrecombining regions, such as Y chromosomes. Contrary to this trend, a new Silene retrotransposon described here, has spread recently all over the genome of plant Silene latifolia, except its Y chromosome. This coincided with the latest steps of sex chromosome evolution in this species.
The integrons In0, In2, and In5 are defective transposon derivatives

The class 1 integrons In0, In2, and In5, found in different locations in pVS1, Tn21, and pSCH884, have closely related structures. All three integrons contain an insertion sequence, IS1326, that is a new member of the IS21 family. IS1326 has caused deletions of adjacent 3'-conserved segment and transposition module sequences, and all three integrons retain a complete copy of only one of four genes required for transposition of related transposons and are thus defective transposon derivatives. In2 contains an additional insertion sequence, IS1353, located within IS1326. IS1353 is a member of the IS3 family and appears to have been acquired after the integron was inserted into an ancestral mercury resistance transposon to create the ancestor of Tn21 and several other transposons that are close relatives of Tn21.
Early Effects of Whole-Body 56Fe Irradiation on Hippocampal Function in C57BL/6J Mice

Relatively little is known about early irradiation effects on hippocampal function in wild-type mice. In this study, the effects of 56Fe irradiation on hippocampal function were assessed starting 2 weeks after whole-body irradiation. Compared to sham irradiation, radiation impaired novel object recognition in female and male C57BL/6J wild-type mice. There were no effects of irradiation on contextual fear conditioning or spatial memory retention in the water maze. It is possible that oxidative damage might contribute to radiation-induced cognitive changes. Therefore, hippocampal and cortical levels of 3-nitrotyrosine (3NT) and lipid peroxidation, measures of oxidative damage were assessed. There were no effects of irradiation on these measures of oxidative damage. As 56Fe irradiation can increase reactive oxygen species (ROS) levels, which may contribute to the impairments in novel object recognition, the effects of the antioxidant alpha-lipoic acid (ALA) on cognition following sham irradiation and irradiation were also assessed. ALA did not prevent radiation-induced impairments in novel object recognition and impaired spatial memory retention of sham-irradiated and irradiated mice in the probe trial after the first day of hidden platform training in the water maze. Thus, the novel object recognition test is particularly sensitive to detect early cognitive effects of 56Fe irradiation through a mechanism unlikely involving ROS or oxidative damage.
Factors associated with the choice of delivery without epidural analgesia in women at low risk in France.

BACKGROUND Regional anesthesia is used for three-fourths of the deliveries in France. Epidural analgesia during labor is supposed to be available to all women at low risk. The purpose of our study was to examine how the choice of delivery without an epidural varied in this context according to women's characteristics, prenatal care, and type of maternity unit. METHODS The 2003 National Perinatal Survey in France collected data about a representative sample of births. We selected 8,233 women who were at low risk and therefore should have been able to choose whether or not to deliver without epidural analgesia. Women were interviewed in the maternity unit after delivery. The factors associated with women's choice to deliver without epidural analgesia were studied with multivariable analyses. RESULTS Of the 2,720 women who gave birth without epidural analgesia, 37 percent reported that they had not wanted one; other reasons were labor occurring too quickly (43.9%), medical contraindication (3.3%), and unavailability of an anesthesiologist (2.8%). The reported decision to deliver without epidural analgesia was closely associated with high parity. It was also more frequent among women in an unfavorable social situation (not cohabiting, no or low-qualified job) and among women who gave birth in non-university public hospitals, in small- or medium-sized maternity units, and in maternity units without an anesthesiologist always on site. CONCLUSIONS Unfavorable social situation and organizational factors are associated with the reported choice to give birth without epidural analgesia. This finding suggests that women are not always in a position to make a real choice. It would be useful to improve the understanding of how pregnant women define their preferences and to know how these preferences change during pregnancy and labor.
Long-term Effects of a Community-wide Hemoglobinopathy Screening Program

We attempted to measure the benefits of a communitywide hemoglobinopathy screening program by reviewing the numbers of newborns detected to have a hemoglobinopathy, the level of utilization of prenatal diagnostic services, and the number of hemoglobinopathies diagnosed prenatally. We measured the effect of our program on 14,051 infants born over a five year period and their families. Results: The incidence of the three common hemoglobinopathies was not altered over this five year period. Only 13% of at-risk couples received prenatal diagnosis, and only 8% of affected infants were diagnosed prenatally. We conclude that our program provided at-risk women with the diagnosis of affected fetuses and the option of possible termination of pregnancy, both of which can be quantified. In addition, our program educated, counseled, and screened large numbers of individuals for hemoglobinopathies resulting in a more educated and informed community.