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Table 2.

Statistic parameters of different samples.

All ρμ, ϖ <  0.25 ρμ, ϖ >  0.25
Sample size 556 869 217 229 339 640
A Mean of Xpm 1.2532 1.2507 1.2547
Uncertainty of mean 0.0009 0.0014 0.0012

Sample size 232 318 80 995 151 323
B Mean of Xpm 1.2512 1.2451 1.2545
Uncertainty of mean 0.0014 0.0024 0.0017

Sample Size 169 745 68 872 100 873
C Mean of Xpm 1.2525 1.2512 1.2534
Uncertainty of mean 0.0016 0.0025 0.0021

Sample size 67 296 32 935 34 361
D Mean of Xpm 1.2642 1.2648 1.2635
Uncertainty of mean 0.0026 0.0037 0.0036

Notes. A. The full sample. B. 232 318 sources with the number of visibility periods under 12. C: 169 745 sources with the number of visibility periods in the domain [13, 16]. D: 67 296 sources with the number of visibility periods over 17.

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