Statistics

The raw data \(x_1, x_2, \ldots \ldots, x_{\mathrm{n}}\) is an A.P. with common difference \(\mathrm{d}\) and first term \(0, \bar{x}\) and \(\sigma^2\) are mean and variance of \(x_{\mathrm{i}}, \mathrm{i}=1,2, \ldots \ldots \mathrm{n}\), then \(\sigma^2\) is