Measurement Section
This section shows the current statistics with respect to each point in the network. These statistics will recompute as the network is ad- justed and recomputed. This measurement-specific information is provided in number of columns which are described below.
The point list is automatically organized in the interface. Points with the highest ranking are listed first. A high ranking indicates a point with a higher chance of problems. Points with lower ranking suggest the target solution is better. However, each column can be sorted from either high to low or low to high by clicking on the column title.
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Weight. Each measurement can have a weight applied. If a point is considered less important or perhaps more erroneous, its weight can be reduced.
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Point. Each point measured by an instrument in the USMN net- work is listed by name.
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Max Err. The maximum error is listed for each point that has been measured by more than one instrument. This depicts the maximum error between any individual measurement of a point and its optimal value.
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Ranking. Displayed as a percentage, this indicates the percentage of the expected 3-sigma envelope consumed by the maximum measurement residual. This is an efficient method of determining which points may have measurement outliers. A point with a ranking of 100% has observations which are consuming the entire 3-sigma envelope. Points with smaller rankings are more tightly clustered around the optimal value. Lower rankings indicate better measurements.
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Ux/Uy/Uz/Umag. The component and magnitude uncertain- ties (in the active coordinate frame) for the optimal point. (These values only appear after an uncertainty field analysis has been performed).
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Meas. A list of the instruments that have observations for a given point. For instance, if a point shows 0 _ _ 3, this indicates that instrument index 0 and 3 each have a measurement for that point, while instruments 1 and 2 do not.
Further detail for a single point can be obtained by double-clicking the point in the list.
The Point Properties dialog displays the contributing shots used to compute the network point. It provides control over:
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Overall Weight. The weight used in the USMN for the point. Specific details on each point are displayed in the following columns:
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Weight. The weighting factor applied to the particular point, this weight is used in the composite point computation.
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Instrument. Instruments that measured the point.
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Error. Component error (Err 1, Err 2, Err 3) shows the error contribution per component.
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Mag. The magnitude error for each point used in the composite point computation.
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Ranking. The percentage of the expected 3-sigma envelope consumed by the maximum measurement residual.