Measures of dispersion or spread give us some idea of how the values of a distribution cluster around the average and to what extent the observations differ from the mean. The three main measures of dispersion of a distribution are the range, the variance and the standard deviation.

Benito Mussolini was an Italian political leader who established fascism in interwar Italy. He held the positions of president of the Council of Ministers of Italy (1922-1943) and leader (Duce) of the Italian Social Republic (1943-1945). His political life began in the ranks of socialism. But after going through World War I, he renounced his Marxist past, turned to the right, and became a nationalist. In 1921 he founded the National Fascist Party and the following year organized the March on Rome, which allowed him to reach power. Little by little, he was building an authoritarian regime that ended the parliamentary system, persecuted opponents, and criticized both capitalism and socialism.