The holmium laser, which operates in a wavelength of 2.1 microns, is highly absorbed by water and has a shallow penetration depth of approximately 0.4 mm. As a pulsed mode laser, the Holmium reduces deeper thermal effects and charring which are more prevalent in Continues Wave lasers (e.g. Thulium, KTP).
In statistical theory, covariance is a measure of how much two random variables change together. In other words, covariance is a measure of the strength of the correlation between two random variables. Also, it can be considered as a generalization of the concept of variance of two random variables.
â¢ Both correlation and covariance are measures of relation between two random variables. Correlation is the measure of strength of the linearity of the two variables and covariance is a measure of the strength of the correlation.â¢ Correlation coefficient values are a value between -1 and +1, whereas the range of covariance is not constant, but can either be positive or negative.t is the most commonly used correlation coefficient and valid only for a linear relationship between the variables. If r=0 no relationship exist, and if râ¥0 the relation is directly proportional; the value of one variable increases with the increase of the other.