Which metric in GNSS quality metrics is explicitly described as better when lower?

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Multiple Choice

Which metric in GNSS quality metrics is explicitly described as better when lower?

Dilution of Precision shows how satellite geometry affects the potential accuracy of a GNSS fix. When the satellites are spread well across the sky, the geometry is favorable and the DOP value is low, meaning the position uncertainty is small. If the satellites line up or cluster in the sky, the geometry is poor and the DOP value rises, indicating greater possible error. Because smaller DOP numbers correspond directly to tighter, more reliable positioning, this metric is described as better when lower. The other options aren't described in the same way. Satellite count is a quantity—the more satellites available, generally the more robust the solution, but there isn’t a universal rule that “lower is better.” Antenna height is just a physical measurement that doesn’t itself define quality. An elevation mask is a threshold used to decide which satellites to include; it’s a setting, and lowering it can actually introduce more low-angle signals that may degrade accuracy rather than improve it.

Dilution of Precision shows how satellite geometry affects the potential accuracy of a GNSS fix. When the satellites are spread well across the sky, the geometry is favorable and the DOP value is low, meaning the position uncertainty is small. If the satellites line up or cluster in the sky, the geometry is poor and the DOP value rises, indicating greater possible error. Because smaller DOP numbers correspond directly to tighter, more reliable positioning, this metric is described as better when lower.

The other options aren't described in the same way. Satellite count is a quantity—the more satellites available, generally the more robust the solution, but there isn’t a universal rule that “lower is better.” Antenna height is just a physical measurement that doesn’t itself define quality. An elevation mask is a threshold used to decide which satellites to include; it’s a setting, and lowering it can actually introduce more low-angle signals that may degrade accuracy rather than improve it.

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