4,382 research outputs found

    Pareto Efficiency in International Taxation

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    This paper addresses a key but neglected task in the theory of international taxation, lent increased urgency by growing awareness of the potential gains from tax coordination: the characterization of Pareto-efficient international tax regimes. It shows that the Diamond-Mirrlees theorem on the desirability of production efficiency, which underlies the key tenets of policy advice in international taxation ? the desirability of destination basis for commodity taxation, of the residence principle for capital income taxation, and of free trade ? is rendered inherently inapplicable to problems of international tax design by the distinctness of national budget constraints that is of the essence in thinking about international taxation. Conditions are established ? relating to the availability of explicit or implicit devices for reallocating tax revenues across countries ? under which production efficiency is nevertheless desirable, and a general characterization developed of the precise ways in which Pareto-efficient international taxation may require violation of established tenets.

    Pareto Efficiency in International Taxation

    Get PDF
    This paper addresses a key but neglected task in the theory of international taxation, lent increased urgency by growing awareness of the potential gains from tax coordination: the characterization of Pareto-efficient international tax regimes. It shows that the Diamond- Mirrlees theorem on the desirability of production efficiency, which underlies the key tenets of policy advice in international taxation--- the desirability of destination basis for commodity taxation, of the residence principle for capital income taxation, and of free trade---is rendered inherently inapplicable to problems of international tax design by the distinctness of national budget constraints that is of the essence in thinking about international taxation. Conditions are established---relating to the availability of explicit or implicit devices for reallocating tax revenues across countries---under which production efficiency is nevertheless desirable, and a general characterization developed of the precise ways in which Pareto efficient international taxation may require violation of established tenets.optimal taxation production efficiency international taxation

    What is the Point: Will Screening Mammography Save my Life?

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    Background: We analyzed the claim mammography saves lives by calculating the life-saving absolute benefit of screening mammography in reducing breast cancer mortality in women ages 40 to 65. Methods: To calculate the absolute benefit, we first estimated the screen-free absolute death risk from breast cancer by adjusting the Surveillance, Epidemiology and End Results Program 15-year cumulative breast cancer mortality to account for the separate effects of screening mammography and improved therapy. We calculated the absolute risk reduction (reduction in absolute death risk), the number needed to screen assuming repeated screening, and the survival percentages without and with screening. We varied the relative risk reduction from 10%–30% based on the randomized trials of screening mammography. We developed additional variations of the absolute risk reduction for a screening intervention, including the average benefit of a single screen, as well as the life-saving proportion among patients with earlier cancer detection. Results: Because the screen-free absolute death risk is approximately 1% overall but rises with age, the relative risk reduction from repeated screening mammography is about 100 times the absolute risk reduction between the starting ages of 50 and 60. Assuming a base case 20% relative risk reduction, repeated screening starting at age 50 saves about 1.8 (overall range, 0.9–2.7) lives over 15 years for every 1000 women screened. The number needed to screen repeatedly is 1000/ 1.8, or 570. The survival percentage is 99.12% without and 99.29% with screening. The average benefit of a single screening mammogram is 0.034%, or 2970 women must be screened once to save one life. Mammography saves 4.3% of screen-detectable cancer patients\u27 lives starting at age 50. This means 23 cancers must be found starting at age 50, or 27 cancers at age 40 and 21 cancers at age 65, to save one life. Conclusion: The life-saving absolute benefit of screening mammography increases with age as the absolute death risk increases. The number of events needed to save one life varies depending on the prospective screening subset or reference class. Less than 5% of women with screen-detectable cancers have their lives saved

    How does age affect baseline screening mammography performance measures? A decision model

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    Background: In order to promote consumer-oriented informed medical decision-making regarding screening mammography, we created a decision model to predict the age dependence of the cancer detection rate, the recall rate and the secondary performance measures (positive predictive values, total intervention rate, and positive biopsy fraction) for a baseline mammogram. Methods: We constructed a decision tree to model the possible outcomes of a baseline screening mammogram in women ages 35 to 65. We compared the single baseline screening mammogram decision with the no screening alternative. We used the Surveillance Epidemiology and End Results national cancer database as the primary input to estimate cancer prevalence. For other probabilities, the model used population-based estimates for screening mammography accuracy and diagnostic mammography outcomes specific to baseline exams. We varied radiologist performance for screening accuracy. Results: The cancer detection rate increases from 1.9/1000 at age 40 to 7.2/1000 at age 50 to 15.1/ 1000 at age 60. The recall rate remains relatively stable at 142–157/1000, which varies from 73– 236/1000 at age 50 depending on radiologist performance. The positive predictive value of a screening mammogram increases from 1.3% at age 40 to 9.8% at age 60, while the positive predictive value of a diagnostic mammogram varies from 2.9% at age 40 to 19.2% at age 60. The model predicts the total intervention rate = 0.013*AGE2 - 0.67*AGE + 40, or 34/1000 at age 40 to 47/1000 at age 60. Therefore, the positive biopsy (intervention) fraction varies from 6% at age 40 to 32% at age 60. Conclusion: Breast cancer prevalence, the cancer detection rate, and all secondary screening mammography performance measures increase substantially with age

    The effect of external forces on discrete motion within holographic optical tweezers

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    Holographic optical tweezers is a widely used technique to manipulate the individual positions of optically trapped micron-sized particles in a sample. The trap positions are changed by updating the holographic image displayed on a spatial light modulator. The updating process takes a finite time, resulting in a temporary decrease of the intensity, and thus the stiffness, of the optical trap. We have investigated this change in trap stiffness during the updating process by studying the motion of an optically trapped particle in a fluid flow. We found a highly nonlinear behavior of the change in trap stiffness vs. changes in step size. For step sizes up to approximately 300 nm the trap stiffness is decreasing. Above 300 nm the change in trap stiffness remains constant for all step sizes up to one particle radius. This information is crucial for optical force measurements using holographic optical tweezers

    Market Power and Cartel Formation: Theory and an Empirical Test

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    Antitrust enforcement makes it difficult to test theories of cartel formation because most attempts to form cartels are blocked. However, federal laws allow U.S. produce growers to operate marketing cartels through devices called marketing orders. These cartels use quantity controls and quality standards to raise prices on fresh produce. Some growers have adopted marketing orders and others have not. This paper develops and tests a positive theory of the adoption of marketing orders. The theory suggests that growers in a region are more likely to adopt a marketing order if the demand for fresh produce is inelastic, the growers’ market share in the fresh market is large, there are barriers to entry and expansion, the fraction of the output the growers ship to the fresh market is not too large or too small, growers are homogeneous, and large cooperatives exist. Probit analyses support these hypotheses.marketing order; cartel; collusion; empirical; agriculture

    Metatarsophalangeal joint pain in psoriatic arthritis: a cross-sectional study

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    Methods. Thirty-four consecutive patients with PsA (mean age 45.3 years, 65% female, mean disease duration 9.9 years) and 22 control participants (mean age 37.9 years, 64% female) underwent clinical and US examination to determine the presence of pain, swelling, synovitis, erosions, effusions and submetatarsal bursae at the MTP joints. Mean barefoot peak plantar pressures were determined at each MTP joint. Levels of pain, US-determined pathology and peak pressures were compared between groups. Binary logistic regression was used to identify demographic, clinical examination-derived, US-derived and plantar pressure predictors of pain at the MTP joints in the PsA group. Results. The presence of pain, deformity, synovitis, erosions (P < 0.001) and submetatarsal bursae and peak plantar pressure at MTP 3 (P < 0.05) were significantly higher in the PsA group. MTP joint pain in PsA was independently predicted by high BMI, female gender and the presence of joint subluxation, synovitis and erosion. Conclusion. These results suggest local inflammatory and structural factors, together with systemic factors (gender, BMI), are predominantly responsible for painful MTP joints in PsA, with no clear role for plantar pressure characteristics
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