If we compare the scatterplot of “baby.sleep v dan.grump” to the scatterplot of “`baby.sleep v dan.sleep”, the overall strength of the relationship is the same, but the direction is different. The cov...If we compare the scatterplot of “baby.sleep v dan.grump” to the scatterplot of “`baby.sleep v dan.sleep”, the overall strength of the relationship is the same, but the direction is different. The covariance between two variables X and Y is a generalisation of the notion of the variance; it’s a mathematically simple way of describing the relationship between two variables that isn’t terribly informative to humans:
If we compare the scatterplot of “baby.sleep v parent.grump” to the scatterplot of “`baby.sleep v parent.sleep”, the overall strength of the relationship is the same, but the direction is different. U...If we compare the scatterplot of “baby.sleep v parent.grump” to the scatterplot of “`baby.sleep v parent.sleep”, the overall strength of the relationship is the same, but the direction is different. Unfortunately, the raw magnitude of the covariance isn’t easy to interpret: it depends on the units in which X and Y are expressed, and worse yet, the actual units that the covariance itself is expressed in are really weird.