Patent ID: 7555381

Claim:
A traffic information providing device for providing traffic information about links located in an area where the traffic information is provided, comprising: a filter basis calculating device which acquires a traffic information history with missing data of a plurality of links located in the area, the traffic information history containing at least the traffic information, performs principal component analysis with missing data for the traffic information contained in the traffic information history to obtain components of traffic information which vary according to correlation between the plurality of links, and outputs the obtained components as feature space basis vectors for a group of such links; a projective norm calculating device which generates a feature space with the output feature space basis vectors as axis vectors, the feature space indicating the correlation between the plurality of links, and calculates a projective norm, which is a norm of a projective vector formed by projecting a vector expressing the plurality of links to the feature space; a correlation filter which compares the calculated projective norm with an interpolation threshold value to determine, based on the result of the comparison, whether or not the missing data can be interpolated for each link, and generates and outputs a list of links to be interpolated which contains the information about the links to be interpolated; an interpolation basis calculating device which, among the traffic information contained in the traffic information history, performs the principal component analysis with missing data for the traffic information of the links to be interpolated to obtain components of traffic information which vary according to correlation between the traffic information of the links to be interpolated, and outputs the obtained components as interpolation bases for the group of links, the principal component analysis with missing data being performed to the links listed in the list of links to be interpolated; a combined coefficient calculating device which calculates combined coefficient bases based on both current traffic information acquired from a probe car and the interpolation bases, and calculates combined coefficients as weights for the combined coefficient bases; and a traffic information estimating device which calculates an estimated value of the traffic information of the links with missing current traffic information data by linearly combining the interpolation bases output by the interpolation basis calculating device.