This article is intended mainly for those people who mistakenly take into consideration the fact that mathematics is all about calculating. Well mathematics is more about how to avoid calculations and make life easier. Yes at times calculations are performed but they are not mathematics but just a...

Statistics Quiz (I)   11) For random error $$varepsilon_i,$$ which of the following constitutes the Gauss-Markov conditions? A) (i) $$E(varepsilon_i)=0$$ (ii) $$E(varepsilon_i ^2)=sigma^2$$ (iii) $$E(varepsilon_i,varepsilon_j)=0, ineq j$$ B) (i) $$E(varepsilon_i)=0$$ (ii) $$E(varepsilon_i ^2)=sigma_i ^2$$ (iii) $$E(varepsilon_i,varepsilon_j)=0, ineq j$$ C) (i) $$E(varepsilon_i)=0$$ (ii) $$E(varepsilon_i ^2)=sigma^2$$ (iii) $$E(varepsilon_i,varepsilon_j)=0, ineq j$$ (iv) $$varepsilon_isim...