History of Portsmouth city to new developments such as Paulsgrove and Leigh Park. On 4 July 1968, an estimated 250,000 people witnessed the return of Alec Rose, a greengrocer in Osborne Road, after he completed his single-handed circumnavigation in "Lively Lady"; he was immediately knighted and made a Freeman of the city. 400 motor-boats, yachts, catamarans and canoes welcomed him into harbour. The University of Portsmouth gained university status in 1992 In 2003 erection was started of a 552 feet high Spinnaker Tower sited at Portsmouth Harbour, and celebrating the city's maritime tradition. Completed in 2005, the tower has twin concrete legs meeting
Effective number of parties Effective number of parties The effective number of parties is a concept introduced by Laakso and Taagepera (1979) which provides for an adjusted number of political parties in a country's party system. The idea behind this measure is to count parties and, at the same time, to weight the count by their relative strength. The relative strength refers to their vote share ("effective number of electoral parties") or seat share in the parliament ("effective number of parliamentary parties"). This measure is especially useful when comparing electoral systems across countries, as is done in the field of political science. The number