8 my $z = 1.96; # 95% confidence interval
11 my $min = ($p + $z * $z / (2 * $n) - $z * sqrt($p * (1 - $p) / $n + $z * $z / (4 * $n * $n))) / (1 + $z * $z / $n);
12 my $max = ($p + $z * $z / (2 * $n) + $z * sqrt($p * (1 - $p) / $n + $z * $z / (4 * $n * $n))) / (1 + $z * $z / $n);
14 $min = 0 if ($min < 0);
23 my (@x) = split /\s+/, $_;
25 my $num_packets = scalar @x;
26 my $num_drops = grep { /\*/ } @x;
28 $buckets{$num_packets}->{'num_bursts'}++;
29 $buckets{$num_packets}->{'num_drops'} += $num_drops;
31 $buckets{$num_packets}->{'bursts_with_drops'}++;
35 for my $n (sort { $a <=> $b } keys %buckets) {
36 my $num_bursts = $buckets{$n}->{'num_bursts'} // 0;
37 my $num_drops = $buckets{$n}->{'num_drops'} // 0;
38 my $bursts_with_drops = $buckets{$n}->{'bursts_with_drops'} // 0;
40 my $drop_rate = $num_drops / ($n * $num_bursts);
41 my $drop_event_rate = $bursts_with_drops / $num_bursts;
43 my ($drop_rate_min, $drop_rate_max) = wilson_interval($num_drops, $n * $num_bursts);
44 my ($drop_event_rate_min, $drop_event_rate_max) = wilson_interval($bursts_with_drops, $num_bursts);
46 printf "%3d: drop_rate %.5f 95%%ci = [%.5f, %.5f] (%4d/%8d) drop_event_rate %.5f 95%%ci = [%.5f, %.5f] (%3d/%4d)\n",
48 $drop_rate, $drop_rate_min, $drop_rate_max, $num_drops, $n * $num_bursts,
49 $drop_event_rate, $drop_event_rate_min, $drop_event_rate_max, $bursts_with_drops, $num_bursts;