A computer-implemented method for determining the amount of an analyte of interest in a sample, the method comprising (a) forming amplification products from an analyte of interest, (b) collecting signal data with a signal measuring device concurrently with the formation of amplification products, the collected signal data comprising periodic measurements of the level of a signal emitted by the sample, wherein the level of signal emitted by the sample corresponds to the amount of amplification products formed by the sample, (c) storing the collected signal data in computer-readable media; and (d) using a computer programmed with an algorithm, which, when executed by the computer, is configured to cause the computer to access the data stored in step (c) and to adjust the data collected in step (b) to remove background contributions to the measured levels associated with sources other than the presence of the analyte of interest, normalize the data adjusted in step (d)(1) by dividing the adjusted data by the maximum level measured, adjusted to remove background contributions, approximate a curve through a portion of the adjusted, normalized data between a predetermined low bound stored on computer-readable media and a predetermined high bound stored on computer-readable media, determine an emergence time at which the curve approximated in step (d)(3) crosses a predetermined threshold data level and determine the amount of the analyte of interest by comparing the emergence time determined in step (d)(4) with threshold times determined for known amounts of the analyte of interest and stored on computer-readable media.