A method of estimating the amount of particulate matter in an exhaust stream comprising the steps of: accumulating a particulate matter on a sensor, wherein the sensor provides a signal that varies based upon an amount of the particulate matter on the sensor; calculating a differential of a conductance signal related to the signal; comparing consecutive differentials to identify an erroneous differential in an abnormal signal based upon an anomaly relating to the accumulation of the particulate matter; and reconstructing the abnormal signal by correcting the erroneous differential to produce a corrected, decimated conductance signal and, wherein the signal is an electrical resistance signal with the anomaly and has an irregular signal shape, and the conductance signal has a generally parabolic shape with the anomalies inducing well-behaved step changes and, wherein the calculating step includes generating a first differential signal from the conductance signal to provide a generally linear signal and, wherein the calculating step is performed at a first sampling frequency, and the reconstructing step is performed at a second sampling frequency that is lower than the first sampling frequency. wherein the reconstructing step includes conforming the erroneous differential to the generally linear signal, which provides a decimated conductance signal that is generally linear, the method further comprising a step of determining a total accumulated particulate matter adjusted for the anomaly, wherein the anomaly corresponds to a large particle strike condition on the sensor, the large particle strike condition causing a sudden increase in the conductance signal, the reconstructing step includes decreasing the erroneous differential to a level represented by a previous, not questionable or already corrected element, or mean or median of previous elements in the measurement sample array, or earlier array if the questionable sample is the first element in a currently processed array and, wherein the total accumulated particulate matter determining step is performed subsequent to the reconstructing step and includes adding in a compensation for the erroneous differential created by large particles, thus retaining the fidelity of the determining step by including the mass of the large particle. accumulating a particulate matter on a sensor, wherein the sensor provides a signal that varies based upon an amount of the particulate matter on the sensor; calculating a differential of a conductance signal related to the signal; comparing consecutive differentials to identify an erroneous differential in an abnormal signal based upon an anomaly relating to the accumulation of the particulate matter; and reconstructing the abnormal signal by correcting the erroneous differential to produce a corrected, decimated conductance signal and, wherein the signal is an electrical resistance signal with the anomaly and has an irregular signal shape, and the conductance signal has a generally parabolic shape with the anomalies inducing well-behaved step changes and, wherein the calculating step includes generating a first differential signal from the conductance signal to provide a generally linear signal and, wherein the calculating step is performed at a first sampling frequency, and the reconstructing step is performed at a second sampling frequency that is lower than the first sampling frequency. wherein the reconstructing step includes conforming the erroneous differential to the generally linear signal, which provides a decimated conductance signal that is generally linear, the method further comprising a step of determining a total accumulated particulate matter adjusted for the anomaly, wherein the anomaly corresponds to a large particle strike condition on the sensor, the large particle strike condition causing a sudden increase in the conductance signal, the reconstructing step includes decreasing the erroneous differential to a level represented by a previous, not questionable or already corrected element, or mean or median of previous elements in the measurement sample array, or earlier array if the questionable sample is the first element in a currently processed array and, wherein the total accumulated particulate matter determining step is performed subsequent to the reconstructing step and includes adding in a compensation for the erroneous differential created by large particles, thus retaining the fidelity of the determining step by including the mass of the large particle.