Franklin D. Roosevelt: Life Before the Presidency. Franklin D. Roosevelt: Life Before the Presidency. Franklin Delano Roosevelt was born to James and Sara Roosevelt in 1882. James was a land-owner and businessmen of considerable, but not awesome, wealth from New York.
How to Measure Variability in Statistics. Statisticians use summary measures to describe the amount of variability or spread in a set of data. The most common measures of variability are the range, the interquartile range (IQR), variance, and standard deviation.
Uncertainty is a situation regarding a variable in which neither its probability distribution nor its mode of occurrence is known. For instance, an oligopolist may be uncertain with respect to the marketÂ­ing strategies of his competitors. Uncertainty as defined in this way is extremely common in economic activity. The function of the entrepreneur is to meet those risks which are non-insurable and which are called uncertainties.