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1.
Philos Technol ; 36(3): 45, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37346393

RESUMO

Algorithmic predictions are promising for insurance companies to develop personalized risk models for determining premiums. In this context, issues of fairness, discrimination, and social injustice might arise: Algorithms for estimating the risk based on personal data may be biased towards specific social groups, leading to systematic disadvantages for those groups. Personalized premiums may thus lead to discrimination and social injustice. It is well known from many application fields that such biases occur frequently and naturally when prediction models are applied to people unless special efforts are made to avoid them. Insurance is no exception. In this paper, we provide a thorough analysis of algorithmic fairness in the case of insurance premiums. We ask what "fairness" might mean in this context and how the fairness of a premium system can be measured. For this, we apply the established fairness frameworks of the fair machine learning literature to the case of insurance premiums and show which of the existing fairness criteria can be applied to assess the fairness of insurance premiums. We argue that two of the often-discussed group fairness criteria, independence (also called statistical parity or demographic parity) and separation (also known as equalized odds), are not normatively appropriate for insurance premiums. Instead, we propose the sufficiency criterion (also known as well-calibration) as a morally defensible alternative that allows us to test for systematic biases in premiums towards certain groups based on the risk they bring to the pool. In addition, we clarify the connection between group fairness and different degrees of personalization. Our findings enable insurers to assess the fairness properties of their risk models, helping them avoid reputation damage resulting from potentially unfair and discriminatory premium systems.

2.
Rev Sci Instrum ; 78(9): 093707, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17902955

RESUMO

A refractive x-ray lens was characterized using a magnifying cone beam setup for differential phase contrast imaging in combination with a microfocus x-ray tube. Thereby, the differential and the total phase shift of x rays transmitted through the lens were determined. Lens aberrations have been characterized based on these refractive properties.

3.
Acta Otolaryngol ; 124(2): 155-64, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15072417

RESUMO

OBJECTIVE: To evaluate the treatment efficacy of an electromechanical middle ear amplifier implant (AI) in patients with chronic moderate-to-severe sensorineural hearing loss (SNHL). The AI is a piezoelectric system with a sound processor and a rechargeable battery within a hermetically sealed titanium canister. Its titanium-sealed microphone is placed in the bony region of the ear canal. The incus-coupled transducer (actuator), which is also inside a titanium casing, is fastened to the adjacent bone. MATERIAL AND METHODS: This was a phase III study comprising 20 intention-to-treat patients. Telemetrical adjustments followed electromechanical amplifier implantations. We used a word recognition test as our primary efficacy measure (Freiburg Speech Recognition Test: DIN 45621). Secondary efficacy measures were the sentence comprehension test (Goettinger Satztest, 1996) for auditory orientation within noisy and quiet environments and a psychosocial adjustment test (Gothenburg Profile Test, 1998). The 6-month follow-up comprised a complete medical examination. Nineteen patients completed the study (per-protocol patients; 100% reference). RESULTS: Seventeen patients (89%) demonstrated improved binaural recognition of phonetically balanced monosyllables. Fourteen postoperative patients (74%) attained a perfect score (100%) on this test, compared to only 3 preoperative patients (16%). Thirteen patients (68%) reached the sentence recognition threshold at a 2:1 dB signal-to-noise ratio during noisy trials. Correct identification of the noise source direction in the horizontal plane occurred in 89% of the trials. The Gothenburg Profile Test scores showed that the subjective evaluation of hearing, orientation, social behavior and self-confidence increased from 48% to 88%. Three patients did not benefit from the implant. CONCLUSION: Treatment of SNHL with a totally implantable hearing system can be an efficient method for those patients unable to wear hearing aids. However, in order to avoid implantation in non-responders, there is a need for more specific audiological indication criteria.


Assuntos
Limiar Auditivo , Perda Auditiva Bilateral/terapia , Perda Auditiva Neurossensorial/terapia , Prótese Ossicular , Ajustamento Social , Percepção da Fala , Audiometria de Tons Puros , Audiometria da Fala , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Seleção de Pacientes , Estudos Prospectivos , Desenho de Prótese , Resultado do Tratamento
4.
Ecotoxicology ; 13(1-2): 29-42, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14992469

RESUMO

The fate of the fungicide carbendazim (applied in the formulation Derosal) in soil was determined in Terrestrial Model Ecosystem (TME) tests and corresponding field-validation studies, which were performed in four different countries (United Kingdom, Germany, Portugal, and The Netherlands). The tests used different soil types, and lasted for 16 weeks. On three of the four sites, grassland soils were used while the fourth site had an arable soil. TMEs consisted of intact soil columns (diameter 17.5 cm; length 40 cm) and were taken from the site where the field study was performed. In the first series of TME tests, carbendazim was applied at four dosages ranging between 0.36 and 77.8 kg a.i./ha, while in the second series of TME tests and the field-validation studies six dosages between 0.36 and 87.5 kg a.i./ha were applied. DT50 values for the dissipation of carbendazim in the TME and field tests were in most cases not significantly affected by the dosage used and ranged between 3.1 and 13.9 weeks in the top 15 cm soil layers. Corresponding DT90 values ranged between 10.1 and 46.1 weeks. DT50 and DT90 values tended to be higher in the more acidic soils of Amsterdam and Flörsheim (pH-KCl 4.8-5.1 and 5.3-5.9, respectively) than in the less acidic soils of Bangor and Coimbra (pH-KCl 5.8-6.6 and 6.4-7.1, respectively). Fate of carbendazim in soil showed similar patterns in the two TME tests and the corresponding field-validation study performed at each site. The only exception was Flörsheim, where the compound was significantly more persistent in the field probably due to different climatic conditions. Carbendazim was not recovered from leachates produced in the TME tests, nor was the compound detected in soil layers deeper than 15 cm. This demonstrates that no significant leaching occurred. This study demonstrates the the TME tests were quite successful in predicting the fate of carbendazim under field conditions.


Assuntos
Benzimidazóis/toxicidade , Carbamatos , Ecossistema , Fungicidas Industriais/análise , Modelos Teóricos , Poluentes do Solo/análise , Clima , Monitoramento Ambiental
5.
Acta Otolaryngol ; 123(6): 683-96, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12953766

RESUMO

OBJECTIVE: To evaluate audiologic selection criteria for incus body coupling (IBC) of a totally implantable middle ear implant (TI-MEI) for the treatment of sensorineural hearing loss (SNHL). MATERIAL AND METHODS: The protocol is specified in the Investigational Device Exemption of a Food and Drug Administration-approved multicenter clinical trial. The prospective study compared pre- and postoperative hearing levels using each patient as their own control. In addition, an implant on/off comparison was made. All patients had a follow-up interval of at least 6 months. Audiologic assessment tests included speech discrimination in quiet as the primary efficacy variable and pure-tone audiometry (aided thresholds), gain, speech recognition in noise and subject satisfaction using standardized questionnaires and visual analog scales (VASs) as secondary efficacy variables. The study group of patients (n = 13) was divided into 3 subgroups based on their pure-tone and speech discrimination scores: Group A consisted of 6 patients, Group B 9 patients and Group C of all 13 patients. All patients suffered from long-standing bilateral moderate to severe SNHL. Five patients were dissatisfied hearing aid (HA) users and eight subjects could not wear HAs. All patients were implanted with a TI-MEI which was coupled to the incus body. The amplification level of the device was set postoperatively using inductive digital fitting based on "most comfortable loudness" specifications. RESULTS: The implant produced median improvements from 30% (optimally fit bilateral HAs; n = 5) and 50% (HA non-users; n = 8) to 70% word recognition at 60 dB SPL. Average word recognition scores at 60, 80 and 90 dB SPL in Groups A and B showed increases from 42% (interquartile range +27%, -12%) to 93.5% (+3%, -5%) and 92.5% (+3%, -7%), respectively. In the presence of background noise, the sentence recognition threshold ranged from -2 to 1 dB signal-to-noise ratio. Maximum amplification was 50 dB at 3 kHz and 55 dB at 4 kHz. In Groups A and B, VASs revealed improvements in both natural sound impression and clarity from 62-70% of a natural sound impression to maximum scores of 100%. Using the standardized Gothenburg profile, subjective evaluations of hearing, orientation, social behavior and self-confidence reached 96-98%, 92-96% and 84-92% of the maximum score for Groups A-C, respectively. CONCLUSIONS: In selected cases, IBC of the TI-MEI investigated herein may be indicated for the treatment of SNHL, provided the following four conditions are met. First, the patient does not derive sufficient benefit from conventional HAs. Second, the specific indication for IBC is restricted to situations that do not allow the coupling of the MEI to the long incus process (e.g. due to an anatomical variation of facial nerve location). Third, IBC is restricted to patients with a steeply sloped moderate to severe high frequency SNHL, amounting to 90 dB HL from 3 to 8 kHz. Patients with low frequency SNHL should not be operated on with the IBC technique, as maximum low frequency hearing loss at 0.5 kHz must not exceed 30 dB. Fourth, Schueller's X-ray should reveal normal mastoid pneumatization. Being restricted to a 6-month follow-up period, this paper provides early clinical results and no clinical evidence of long-term efficiency of the implant.


Assuntos
Perda Auditiva Neurossensorial/cirurgia , Bigorna/cirurgia , Prótese Ossicular , Procedimentos Cirúrgicos Otológicos/métodos , Seleção de Pacientes , Adulto , Audiometria/métodos , Limiar Auditivo/fisiologia , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Estudos Prospectivos , Recuperação de Função Fisiológica
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