1) Find the first four moments about the value 8 for the set of observations: 5,7,8,8,10,11.
2)Find the first four moments about zero for the set of observations : -3,-2,1,3,4.
3) Find the first four moments about mean for the set of observations: 16,19,22,23,25.
4) The first four raw moments of a distribution are 0.9,1.7,3.1 and 8.2 respectively. Find the first four central moments of the distribution.

Dear Student,
Please find below the solution to the asked query:

2. We have:-3,-2,1,3,4We want first four moments about 0.
x x-0=x (x-0)2=x2 (x-0)3=x3 (x-0)4=x4
-3 -3  9 -27 81
-2 -2 4 -8 16
1 1 1 1 1
3 3 9 27 81
4 4 16 64 256
Total 3 39 57 435

Let m1,m2,m3 and m4 be first four momentsm1=xn=35m2=x2n=395m3=x3n=575m4=x45=4355=733. We have 16,19,22,23,25Meanx¯=16+19+22+23+255=1055=21
x x- (x-)2 (x-)3 (x-)4
16 -5 25 -125 625
19 -2 4 -8 16
22 1 1 1 1
23 2 4 8 16
25 4 16 64 256
Total 0 50 -60 914

Let m1,m2,m3 and m4 be first four momentsm1=x-x¯n=05=0m2=x-x¯2n=505=10m3=x-x¯3n=-605=-12m4=x-x¯45=9145=182.8Please post your other queries in different thread and only one query in one thread.
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