Mean. The mean of an observation variable is a numerical measure of the central location of the data values. It is the sum of its data values divided by data count. Hence, for a data sample of size n, its sample mean is defined as follows:Similarly, for a data population of size N, the population mean is:ean. The mean of an observation variable is a numerical measure of the central location of the data values. It is the sum of its data values divided by data count. Hence, for a data sample of size n, its sample mean is defined as follows:
Names of territorial origin were common, a man would have had the surname Langford if he was from the village of Langford. An example of this is Osm' de Langeford who was recorded in the Pipe Rolls for Wiltshire in 1130. The name Osm' de Langeford means Osm' from the village of Langford.
This interesting surname is of Anglo Saxon origin, and is a locational name from places called Marsden in Lancashire, and the West Riding of Yorkshire, deriving from the Olde English pre 7th Century mearc meaning boundary, and denu, valley; hence, a valley forming a natural boundary.he first recorded spelling of the family name is shown to be that of Alan de Marchesden, which was dated 1246, witness in the Assize Court Rolls of Lancashire, during the reign of King Henry 111, known as The Frenchman, 1216 - 1272.