API Snapshots: Core, Memory, Pig, Hive, Misc

Table of Contents

Choosing Desired Relative Error For Theta Sketches

Quick Select Sketch (Default)

Number of Std Dev 1 2 3
Confidence Interval 68.27% 95.45% 99.73%
Nominal Entries (k) : Formula -> 1/sqrt(k-1) 2/sqrt(k-1) 3/sqrt(k-1)
16 25.82% 51.64% 77.46%
32 17.96% 35.92% 53.88%
64 12.60% 25.20% 37.80%
128 8.87% 17.75% 26.62%
256 6.26% 12.52% 18.79%
512 4.42% 8.85% 13.27%
1,024 3.13% 6.25% 9.38%
2,048 2.21% 4.42% 6.63%
4,096 1.56% 3.13% 4.69%
8,192 1.10% 2.21% 3.31%
16,384 0.78% 1.56% 2.34%
32,768 0.55% 1.10% 1.66%
65,536 0.39% 0.78% 1.17%
131,072 0.28% 0.55% 0.83%
262,144 0.20% 0.39% 0.59%
524,288 0.14% 0.28% 0.41%
1,048,576 0.10% 0.20% 0.29%

Alpha Sketch

Number of Std Dev 1 2 3
Confidence Interval 68.27% 95.45% 99.73%
Nominal Entries (k) : Formula -> 1/sqrt(2k) 2/sqrt(2k) 3/sqrt(2k)
512 3.13% 6.25% 9.38%
1,024 2.21% 4.42% 6.63%
2,048 1.56% 3.13% 4.69%
4,096 1.10% 2.21% 3.31%
8,192 0.78% 1.56% 2.34%
16,384 0.55% 1.10% 1.66%
32,768 0.39% 0.78% 1.17%
65,536 0.28% 0.55% 0.83%
131,072 0.20% 0.39% 0.59%
262,144 0.14% 0.28% 0.41%
524,288 0.10% 0.20% 0.29%
1,048,576 0.07% 0.14% 0.21%