Search results for "portion"
showing 10 items of 902 documents
Bicausative matrices to measure structural change: Are they a good tool?
1999
The causative-matrix method to analyze temporal change assumes that a matrix transforms one Markovian transition matrix into another by a left multiplication of the first matrix; the method is demand-driven when applied to input-output economics. An extension is presented without assuming the demand-driven or supply-driven hypothesis. Starting from two flow matrices X and Y, two diagonal matrices are searched, one premultiplying and the second postmultiplying X, to obtain a result the closer as possible to Y by least squares. The paper proves that the method is deceptive because the diagonal matrices are unidentified and the interpretation of results is unclear. Keywords : Input-Output ; Ch…
Forecast Output Coincidence and Biproportion: Two Criteria to Determine the Orientation of an Economy. Comparison for France (1980-1997)
2002
International audience; The method of forecast output coincidence used to determine if sectors are demand-sided or supply-sided in an input-output framework mixes two effects, the structural effect (choosing between demand and supply side models) and the effect of an exogenous factor (final demand or added-value). The note recalls that another method is possible, the comparison of the stability of technical and allocation coefficients, generalized by the biproportional filter: if for a sector, after biproportional filtering, column coefficients are more stable than row coefficients, then this sector is declared as not supply-sided (but one cannot decide that it is demand-sided anyway), and …
The variations of technical and allocation coefficients : are they comparable really ?
1995
Two great alternative hypothesis are possible in the analysis input-output : the model may be demand-driven (Leontief) or supply-driven (Ghosh). To test the consistency of these hypotheses on the long term, this paper studies the interest of proportional filters (comparison of column or row coefficients) and the interest of the biproportional filter for the temporalcomparison of input-output matrices. An application is proposed for France between 1980 and 1993. The result is the following : in the long period, there are more sectors supply-driven than demand-driven (i.e. row coefficients are less variable than column coefficients for the majority of the sectors). (FRE) Deux grandes hypothès…
A biproportional filter to compare technical and allocation coefficient variations
1997
International audience; In input-output analysis there are two alternate possibilities between Leontief's mechanism (fixed technical coefficients) and Ghosh's mechanism (fixed allocation coefficients). Testing the long term consistency of these mechanisms entails comparing input-output matrices over time. This paper challenges the value of proportional filters (separate comparison of column and row coefficients) and introduces the biproportional filter which allows simultaneous comparison of column and rows. An application is proposed using French input-output tables for 1980 and 1993. The stability of column coefficients cannot be taken for granted and generally, for any sector, both rows …
The biproportional factorial analysis
1993
Beyond the Factorial Analysis of Correspondences, the paper presents a newmethod of data analysis: the Biproportional Factorial Analysis. In the Factorial Analysis of Correspondences, the matrix to be diagonalised is the product o f the two matrices o f profiles, row and columns: this matrix is not symmetrical. In the Biproportional Factorial Analysis, the matrix to be diagonalised is the symmetrical product o f an intermediate matrix over itself; this intermediate matrix is calculated as the biproportion o f the data matrix over normalisedmargins. This provides a full symmetry between rows and columns. After recalling the Factorial Analysis of Correspondences, the paper recall what it is b…
About the criteria of output coincidence for forecasts to determine the orientation of the economy (application for France, 1980-1997)
2000
This note indicates that the method of output coincidence for forecasts used to determine if sectors are demand-driven or supply-driven in an input-output framework mixes two effects, the structural effect (choosing between demand and supply driven models) and the effect of an exogenous factor (final demand or added-value). The note recalls that another method is possible, the comparison of the stability of technical and allocation coefficients, generalized by the biproportional filter: if for a sector, after biproportional filtering, column coefficients are more stable than row coefficients, then this sector is declared as not supply-driven (but one cannot decide that it is demand-driven a…
Effects of a Mediterranean Eating Plan on the Need for Glucose-Lowering Medications in Participants With Type 2 Diabetes: A Subgroup Analysis of the …
2019
OBJECTIVE: To examine the effects of two Mediterranean eating plans (Med-EatPlans) versus a low-fat eating plan on the need for glucose-lowering medications. RESEARCH DESIGN AND METHODS: From the Prevención con Dieta Mediterránea (PREDIMED) trial, we selected 3,230 participants with type 2 diabetes at baseline. These participants were randomly assigned to one of three eating plans: Med-EatPlan supplemented with extra-virgin olive oil (EVOO), Med-EatPlan supplemented with mixed nuts, or a low-fat eating plan (control). In a subgroup (15%), the allocation was done in small clusters instead of using individual randomization, and the clustering effect was taken into account in the statistical a…
Insulin resistance and atrial fibrillation (from the Framingham Heart Study)
2011
Diabetes mellitus and obesity are increasing in prevalence and are associated with an elevated risk of atrial fibrillation (AF). Given the aging of the United States population, AF is projected to concomitantly increase in prevalence in the upcoming decades. Both diabetes and obesity are associated with insulin resistance. Whether insulin resistance is an intermediate step for the development of AF is uncertain. We hypothesized that insulin resistance is associated with an increased risk of incident AF. We examined the association of insulin resistance with incident AF using multivariate Cox proportional hazards regression analysis adjusting for the established AF risk factors (i.e., age, g…
Procalcitonin and long-term prognosis after an admission for acute heart failure
2014
Abstract Background Traditionally, procalcitonin (PCT) is considered a diagnostic marker of bacterial infections. However, slightly elevated levels of PCT have also been found in patients with heart failure. In this context, it has been suggested that PCT may serve as a proxy for underrecognized infection, endotoxemia, or heightened proinflammatory activity. Nevertheless, the clinical utility of PCT in this setting is scarce. We aimed to evaluate the association between PCT and the risk of long-term outcomes. Methods and results We measured at admission PCT of 261 consecutive patients admitted for acute heart failure (AHF) after excluding active infection. Cox and negative binomial regressi…
The impact of oophorectomy on survival from breast cancer in patients with CHEK2 mutations
2022
BACKGROUND: To estimate the impact of oophorectomy and other treatments on the survival of breast cancer patients with a CHEK2 mutation. METHODS: Women with Stage I–III breast cancer who were treated at 17 hospitals in Poland were tested for four founder mutations in the CHEK2 gene. 974 women (10%) were positive for a CHEK2 mutation. Control patients without a CHEK2 mutation were selected from a database of patients treated over the same time period. Information on treatments received and distant recurrences were retrieved from medical records. Treatments included chemotherapy, hormonal therapy (tamoxifen) and radiation therapy. Oophorectomies were performed for the treatment of breast canc…