Celestial navigation Celestial navigation Celestial navigation, also known as astronavigation, is the ancient and modern practice of position fixing that enables a navigator to transition through a space without having to rely on estimated calculations, or dead reckoning, to know their position. Celestial navigation uses "sights", or angular measurements taken between a celestial body (e.g. the Sun, the Moon, a planet, or a star) and the visible horizon. The Sun is most commonly used, but navigators can also use the Moon, a planet, Polaris, or one of 57 other navigational stars whose coordinates are tabulated in the nautical almanac and air almanacs.
Abnormal return where: AR - abnormal return for firm i on day t R - actual return for firm i on day t E(R) – expected return for firm i on day t A common practice is to standardise the abnormal returns with the use of the following formula: formula_3 where: SAR - standardised abnormal returns SD – standard deviation of the abnormal returns The SD is calculated with the use of the following formula: formula_4 where: S – the residual variance for firm i, R – the return on the stock market index on day t, R – the average return