Estimating the conditional standard deviation of some living standard 

The following figure shows a scatter plot of the beninese household expenditures for 1996 and 1999. 
To show the conditional standard deviation of these expenditures: 


One can normalise this standard deviation by the expected level of Y (the expected total expenditures in the final period at a given level for the initial period). To do this, select the option "Normalised by the expected value of Y" 


Instead of initial income, one can use average income of the household across the two years. 
