BX

This screenshot is from an Open University broadcast (BBC2 Television, December 1973),
module ES103 (Economics and Social Studies Foundation Course, Programme 3).
The computer-drawn graphic clearly expounds the straight-line law between x = consumption 
(the independent variable) and y = happiness (the dependent variable).
The linear relationship predicted by theory clearly shows up errors in 
the experimental data points obtained by OU students at the 1973 Summer School, 
held annually in Milton Keynes.