Juan Manuel Pérez Salamero González

The continuous sample of working lives: improving its representativeness

This paper studies the representativeness of the Continuous Sample of Working Lives (CSWL), a set of anonymized microdata containing information on individuals from Spanish Social Security records. We examine several CSWL waves (2005–2013) and show that it is not representative for the population with a pension income. We then develop a methodology to draw a large dataset from the CSWL that is much more representative of the retired population in terms of pension type, gender and age. This procedure also makes it possible for users to choose between goodness of fit and subsample size. In order to illustrate the practical significance of our methodology, the paper also contains an application in which we generate a large subsample distribution from the 2010 CSWL. The results are striking: with a very small reduction in the size of the original CSWL, we significantly reduce errors in estimating pension expenditure for 2010, with a p value greater or equal to 0.999.

A Procedure for Selecting Representative Subsamples of a Population from a Simple Random Sample

This paper proposes a procedure for selecting large subsamples drawn from a large simple random sample that are more representative of the population under study. By means of the so-called constant of proportionality, the procedure seeks to maximize the size of the subsample taken from a stratified random sample with proportional allocation, restricting it to a p-value high enough to achieve a good fit using Pearson’s chi-square goodness of fit test. The user has the freedom to choose between a larger subsample with poorer adjustment or a smaller subsample with a better fit. We use the Continuous Sample of Working Lives (CSWL), a set of micro data taken from Spanish Social Security records, to illustrate the procedure, finding large subsamples with better representativeness than the original. The advantages of using this sample selection design procedure can be seen by comparing the estimate of total pension expenditure provided by the CSWL and that provided by the subsamples obtained. Having large subsamples that are more representative leads to better quality in any subsequent analysis of the sustainability of public pension systems.

Evaluación de las tarifas de las pensiones de accidentes de trabajo y enfermedades profesionales (2011-2015) (Are the Rates Levied to Cover the Cost of Pensions for Occupational Injury and Disease Actuarially Fair? An Analysis for the Period 2011-2015))

Spanish Abstract: Este trabajo analiza si las tarifas que se aplican para la determinacion del denominado “capital coste” de pensiones derivadas de los accidentes de trabajo (AT) y enfermedades profesionales (EP) son las adecuadas, y si la falta de actualizacion periodica ha producido distorsiones financieras entre los actores implicados. A partir de los datos de la Muestra Continua de Vidas Laborales (MCVL) y de la evolucion de la longevidad de la poblacion general en Espana, se estiman tablas de mortalidad para las contingencias de viudedad e invalidez, que combinadas con los parametros economicos y financieros apropiados, permiten construir las bases tecnicas actuarialmente justas para cada uno de los anos objeto de analisis. Los resultados obtenidos sugieren que las tarifas aplicadas en el periodo 2011-2014 han sido muy superiores a las que se deberian haber aplicado, lo que habria originado una transferencia encubierta de recursos de las Mutuas Colaboradoras de la Seguridad Social (MCSS) hacia la Tesoreria General de la Seguridad Social (TGSS). Se concluye que es urgente articular un procedimiento de revision periodica anual que adapte los elementos fundamentales de la tarifa a las cambiantes condiciones financieras, economicas y demograficas.English Abstract: This paper analyses whether the rates levied to cover the actuarial cost of pensions deriving from occupational injury and disease are the appropriate ones, or whether the absence of regular updating has given rise to financial imbalances between the parties involved. Using data from the Continuous Sample of Working Lives and the evolution of life expectancy for the general population in Spain, we estimate mortality tables for widowhood and invalidity pensions which, combined with the appropriate economic and financial parameters, will enable us to create an actuarially fair technical basis for each year to be analysed. The results obtained suggest that the rates levied during the period 2011-2014 were much higher than they should have been and resulted in a hidden transfer of resources from the Mutual Insurance Societies for Occupational Accidents and Diseases to the General Treasury of Social Security. We conclude that there is an urgent need for a periodic review procedure to ensure that the main elements of the rate established keep pace with changing financial, economic and demographic conditions.

Un Procedimiento De Selección De Sub-Muestras De Gran Tamaño De Una Muestra Aleatoria Simple Representativas De La Población De Estudio (A Selection Procedure of High Size Sub-Samples from a Simple Random Sample Representative of the Population)

Spanish Abstract: En este trabajo se propone una metodologia basada en la optimizacion para elegir sub-muestras de gran tamano extraidas de una muestra aleatoria simple inicial que mejore la representatividad de la poblacion objeto de estudio. El criterio se basa en maximizar el tamano de la sub-muestra a traves de la constante de proporcionalidad de un muestreo estratificado con afijacion proporcional sujeto a que el p-valor del test de bondad del ajuste tome valores suficientemente altos, dejando al usuario la posibilidad de elegir la relacion deseada entre la calidad del ajuste y el tamano de la sub-muestra. Para ilustrar el procedimiento propuesto se realiza una aplicacion a la Muestra Continua de Vidas laborales (MCVL). Se confirma que es posible disponer de sub-muestras de gran tamano con una representatividad muy mejorada lo que permite obtener mayor calidad en los posteriores analisis sobre el sistema publico de pensiones. La mejora en la representatividad de la sub-muestra obtenida se constata comparando la estimacion del gasto total en pensiones proporcionada por la MCVL y la de dicha sub-muestra.English Abstract: This paper proposes criteria for choosing large sub-samples drawn from a large simple random sample that are more representative of the population that is the object of the study. The criterion used seeks to maximize the size of the sub-sample restricted to a p-value high enough to achieve a good fit of the test for goodness of fit, giving the user the freedom to choose between a larger size sub-sample with a poorer adjustment or a better fit with smaller size. We use the Continuous Sample of Working Lives (CSWL) to illustrate the procedure finding high size sub-samples with better representativeness The gains from using this sample design procedure is found by comparing the estimate of total pension expenditure provided by the CSWL and such sub-samples. Having most representative large sub-samples is possible allowing for higher quality in subsequent analysis on the public pension system