Q.

Let x¯, M and σ2 be respectively the mean, mode and variance of n observations x1,x2,…,xn and di=-xi-a,  i=1,2,…,n where a is any number.

Statement 1:  Variance of d1,d2,…,dn is σ2.

Statement 2:  Mean and mode of d1,d2,…,dn are -x¯-a and -M-a respectively.

1 Statement 1 and Statement 2 are both false  
2 Statement 1 and Statement 2 are both true  
3 Statement 1 is true and Statement 2 is false  
4 Statement 1 is false and Statement 2 is true  

Ans.

(2)

S1→V(ax+b)=a2V(x)

S2→mean(ax±b)=a mean(X)±b

Mode(x1,x2,…,xn)=K

Mode(ax1±α,ax2±α,…,axn±α)=ak±α

Central tendencies depend on shift of origin & scaling

Variance depends on scaling but not shift of origin