Essential data Essay Example | Topics and Well Written Essays - 2500 words

Essential data - Essay Example annual sales of SVL 12†, 15† and 19† flat screens of computers, the chart shows that the annual sale of Type C screens that are 19† are greater than sales of type B and type a it is obviously because the 19† screens are expensive than 12† and 15†. The correlation is one of the most common and most useful statistics. A correlation r is a single value that explains the degree of relationship among two variables. Correlation value r will always be between -1.0 and +1.0, if the correlation is negative, we have a negative relationship; if its positive, the relationship is positive. Here we have the correlation value r = -0.786 and the scatter plot shows a negative association between distance of SVL outlet and the Total sales in SVL outlets, it means the sales in SVL outlets that are near to high streets is more than in those outlets that are far from the high street. The correlation value r = 0.772 and the scatter plot shows a positive association between average monthly advertising expenditure and the Total sales in SVL outlets, it means the sales in SVL outlets increases with the expenditure on advertising. Regression investigates the dependence of one variable conventionally called the dependent variable on one or more variables called independent variable and provide an equation to be used for estimating or predicting the average value of the dependent variable from the known values of independent variable. Where, Y is the predictor, X is the predictor, â€Å"a† is the value of Y when X equals zero and is called Y-intercept, and â€Å"b† indicates the changes in Y for a unit change in X and is called the slope of the line and â€Å"e† is an error term having a normal distribution with mean of zero and standard deviation ÏÆ' (Fisher, 1922). We estimate â€Å"a† by â€Å"a†, â€Å"b† by â€Å"b† and â€Å"ÏÆ'† by â€Å"s†. The fitted equation is then: If we have P-value < ï  ¡ then we have to reject our hypothesis, from ANOVA table of regional location and