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Re: HO 211 (Ageton) sight reduction accuracy
From: Paul Hirose
Date: 2019 May 12, 14:27 -0700
From: Paul Hirose
Date: 2019 May 12, 14:27 -0700
On 2019-05-11 9:32, Robert VanderPol II wrote: > I was wondering if you would do the statistical analysis for a 1' of arc table, no interpolation, no Sadler, with statistical results provided for LHA 0°-9°59', 10°-19°59', etc, up to 80°, then every 5° up to 90°? You didn't say anything about the precision of the tabulation, so I followed the format of the Bayless table, which also has a 1-minute interval. Its A function is given in whole numbers up to 85°. At that angle and beyond, precision increases to tenths. There's a corresponding change in the B precision. Also, you didn't mention any constraints on latitude and altitude, so I'll be consistent with my 2016 data: latitude 0 to 70, altitude 5 to 80. Statistics are root mean square altitude error, percentage of altitude errors greater than a half minute, maximum altitude error, root mean square azimuth error, percentage of azimuth errors greater than a half degree, and maximum azimuth error. For each range of meridian angle t, I generated 100,000 simulated observations and solutions. Maximum errors are statistical aberrations and can vary considerably from one run to another, even with no change to the parameters. alt alt alt az az az RMS >.5' max RMS >.5° max 0.57' 39.30% 2.0' 0.86' 0.00% 0.4° t 0-10 0.56' 38.34% 2.1' 5.81' 0.70% 2.8° t 10-20 0.54' 36.91% 2.1' 6.09' 0.89% 2.3° t 20-30 0.54' 36.13% 2.2' 5.40' 0.76% 1.8° t 30-40 0.54' 36.09% 2.6' 5.01' 0.70% 1.5° t 40-50 0.55' 37.45% 2.6' 4.52 0.59% 1.3° t 50-60 0.60' 40.42% 3.7' 3.98' 0.48% 1.2° t 60-70 0.78' 48.55% 4.8' 3.24' 0.22% 1.0° t 70-80 1.37' 63.14% 11.6' 2.58' 0.04% 0.7° t 80-85 8.91' 85.77% 44.6' 5.91' 0.66% 1.0° t 85-90