mpxsmooth utility

Previously when weights were generated by the weight generation process, there was almost always a need for manually editing the weights to make them optimal for the implementation. This process is called weight "smoothing". Smoothing is accomplished by reading the matched and unmatched sampling binary data generated by the mpxcomp utility. The utility reads this binary data and applies any necessary adjustments to ensure a smoothed output. The data is considered smoothed when the sample data is monotonically decreasing for msamps (matched samples) and increasing for usamps (unmatched samples). This output can then be used with the mpxwgts utility to generate the smoothed weights used by the operational server. The smoothing process applies only to data that represents one-dimensional (1DIM), two-dimensional (2DIM), and three-dimentional (3DIM) weights.

The reason the sampling data files are generally non-monotonically increasing and decreasing is because of irregular counts in the unmatched and matched samples where they are not expected. Fixing the discrepancy before running the weight generation step where the final weights are computed ensures smoothed weights. The process begins by setting all input values to wgtFLR if they are less than this value. Next, each value is compared with its nearest neighbor to determine if an adjustment must be made. If an adjustment is needed, the slope (derivative) and the mid point of these two values are calculated. The result of these calculations is used to correct the current and next sampling data value. This process is repeated until the data monotonically increases or decreases.

The mpxsmooth utility eliminates the need for manual intervention. The weight generation utility, which is started from InfoSphere® MDM Workbench or by using the madconfig generate_weights target, automatically runs this utility. The only time you might run mpxsmooth is when you already have the matched sample and unmatched sample binary files from a previous weight generation and want to smooth them. Manually running mpxsmooth requires that you also run the mpxwgts utility.

If the bxmOutDir option is not provided, then a view of the before and after smoothing process is dumped to stdout (console). Both Usamp and Msamp options can be provided at the same time. Remember that this utility replaces the original binary and text files if the bxmOutDir setting is the same as bxmInpDir.

Before you run a utility, make sure that you have set the necessary operational server environment variables. For information about the variables, see the operational server environment variables topic.