Data available for profit (₹ Thousands) of a company as
Based on the above data using least square method the trend value for the year '2007' is |
147.64 138.86 130.57 131.22 |
138.86 |
The correct answer is Option (2) → 138.86 ** Least Squares Trend for 2007 Given 7 years: 2004–2010 Profits (₹000): 114, 130, 126, 144, 138, 156, 164 Let 2007 be the central year → assign: $\begin{aligned} 2004 &\to x=-3\\ 2005 &\to x=-2\\ 2006 &\to x=-1\\ 2007 &\to x=0\\ 2008 &\to x=1\\ 2009 &\to x=2\\ 2010 &\to x=3 \end{aligned}$ Sum of $y$: $114+130+126+144+138+156+164=972$ Sum of $xy$: $-3(114)=-342$ $-2(130)=-260$ $-1(126)=-126$ $0(144)=0$ $1(138)=138$ $2(156)=312$ $3(164)=492$ Total: $-342-260-126+0+138+312+492=214$ Trend equation: $\hat{y}=a+bx$ where $a=\frac{\sum y}{n}=\frac{972}{7}=138.857$ $b=\frac{\sum xy}{\sum x^{2}}=\frac{214}{28}=7.643$ For year 2007, $x=0$: $\hat{y}=a+bx=138.857+7.643(0)=138.857$ Trend value for 2007 ≈ 138.86 (₹ thousand) |