what does $lambda_u = 0.5$ mean tail dependence coefficient what is the tail dependencies in a graph? what does the lower coefficient mean for a coefficient what is the tail dependence coefficient what does higher or lower coefficient mean what is tail dependency mean what if l means higher or lower coefficient? what does it mean when you have coefficients above the tail? what does it mean when your tail rely on one coefficient does $lambda_u mean the tail what does it mean when a coefficient above or below 0.5 is the tail dependence coefficient? what is tail dependence coefficient what does tail dependence coefficients mean what does it mean when the tail dependence what does lower coefficients mean what does $lambda_u mean what does higher or lower coefficients mean tail dependence coefficients in ohsp tail dependence coefficient