ESTUDIO COMPARATIVO DEL CÁLCULO DEL PUNTO DE REORDEN CON LA DEMANDA Y EL TIEMPO DE ENTREGA POISSONIANOS Y CORRELACIONADOS

Abstract

This paper presents a comparative study of calculating the reorder point when the daily demand for goods is correlated with lead
time and both variables have a Poisson probability distribution and when variables are uncorrelated.
For the illustrative case, there has been difference of reorder point calculated with both methods, which is due to correlation
between the variables is significant.
If correlation coefficient takes negative or positive high values, then the differences in calculated reorder point with the two
methods are significant. These differences also depend on the service level managed.
If the correlation coefficient is positive, the traditional methodology underestimates the reorder point and it overestimates if the
correlation is negative.
Therefore it is recommended that before estimating the reorder point, to calculate the correlation coefficient between the two
variables and apply the Wang equations if the coefficient falls between -0.4 and -1 or between 0.4 and 1.
The minimum inventory cost was obtained with a correlation coefficient of 0.4, which depends on the cost structure of stockouts
and maintenance. If the stockout cost is high compared to the maintenance, the minimum cost is obtained with a higher value of
the correlation coefficient.