1. A method for increasing accuracy in estimating an average time taken to travel through a chosen road segment, the method comprising: a road traffic sensing system collecting data corresponding to one or more vehicles travelling through road segments, thereby enabling determination of a time taken by the one or more vehicles to travel through the road segments; at least one processor identifying one or more correlated road segments for which the time taken to travel through the correlated road segments is correlated with the time taken to travel through the chosen road segment, the processor identifying one or more preferred road segments among the correlated road segments that increases the accuracy in determining the average time taken to travel through the chosen road segment; and the processor estimating the average time taken to travel through the chosen road segment using data corresponding to a time taken to travel through the preferred road segments and using data corresponding to the time taken to travel through the chosen road segment, characterized in that identifying the preferred road segments comprises: identifying the correlated road segments which comprise exclusive vehicles for which the time taken to travel is known for the correlated road segments and for which the time taken to travel is not known for the chosen road segment; estimating the time taken to travel by each of the exclusive vehicles on the chosen road segment using the correlation between the correlated road segments and the chosen road segment; determining, for each of the correlated road segments, an improvement that is achieved in estimating the average travel time by using data corresponding to an estimated time taken to travel by each of the exclusive vehicles on the chosen road segment; sorting the correlated road segments based on the improvement achieved in estimating the average travel time; and determining a reduction in error in estimating the average time taken to travel through the chosen road segment by using the time taken by exclusive vehicles, by considering the correlated road segments in decreasing order of reduction in error, till one of the correlated road segments does not reduce the error in the estimate compared to the reduction in error by the previous correlated road segment which provided the reduction in error, wherein the correlated road segments which provided the reduction in error in estimate are considered as preferred road segments wherein estimating the time taken to travel by each of the exclusive vehicles on the chosen road segment using the correlation between the correlated road segments and the chosen road segment is derived using the equation: 
 Y ( j ) 1 =f ( X ( j )),1 ≦j≦N, wherein N is the number of exclusive vehicles corresponding to one of the correlated road segments, X(j) is the time taken to travel by the J th exclusive vehicle through the one of the correlated road segments, Y(j) 1 is the estimated time taken to travel through the chosen road segment by each of the J th exclusive vehicles, and f is a function.