WorksheetsBusiness statistics - II
Total questions: 15
Worksheet time: 23mins
regression analysis which confines it self to study of only two variables is called ____________
regressor
predictor
regression
dependent
X-x̄ = (a) (Y-Y) x on y
y on x is (b) (x-x̄)
γσxσy
xy
Arithmetic mean is 36 of x and y is 85 Standard deviation 11 of x and y is 8. Correlation is 0.66 find X on Y?
x = 0.9075 , Y is -41.1375
X = 0.365 y = 22.48
x = 13.88 y = 17.5
To calulate stright line trend method
year
year
y
production
x
x value
xy
production and x Value
x2
x2
Yc = a+bx
least square
(3x1)+(3x2)+(4x1)
weighted moving average
2+4+5+3
4 yr moving average
2+3+1
3 yr moving average
1+2+3+5/4
semi Average
draw free hand trend line
year : 1 , 2 , 3
production : 100 , 120, 130
A= ΣY/N B= (a) so Yc = (b)
Σx2Σxy
year : 1982, 1983, 1984
Production : 77, 88, 94
find lease square method
y = 45+2.5x year origin is 1996 to 1999 find straight line
yc = 52.5+2.5x
yc = 62.5+2.5x
yc = 53.5+2.5x
yc = 50.5+2.5x
estimate the value for 1980
y=45+2.5x year of origin is 1996 to 1999 so (a) +2.5x
fitting a second degree parabola trend
y = a+bx+cx2
so Σy = (a)
years = 1971,72,73,74,75,76,77
y = 7,10,17,28,43,62,85
x = ?
find xy = for all the years in least square method
Find Trend equation for Y = 35+5x+3x2
calculate three year weighted moving average for 1,4,1
values are 2,6,1,5,3,7,2 so what is the first value of weighted moving average?
4.5
2.5
4.0
5.5
Σy = na
+bΣx
cΣx2
Σxy=aΣx+
bΣx2+cΣx3
