Explain this to me

This table contains stats for heroes' picks and bans.
Rank is used to sort heroes by winrate, taking number of their picks and bans into account. Higher rank means the hero is stronger. Rev-Rank (Reverse Rank) is used to show the least effective heroes with the most number of matches.
Number of bans is calculated approximately based on ratio of matches on the position to all matches of the hero.
Balance metric estimates how balanced the meta is (0 to 100)

Median hero picks (mp): 1 - Median hero bans (mb): 1 - Matches: 22

Remove low picks (0.9mp) Remove low bans (0.9mb)

Balance rank	Winrate	Pickrate	Contest Rate
1.8	3.6	0.0	0.0

Hero	Position	Matches	Contest Rate	Rank	Rev-Rank	Picked	Winrate	mp	Banned	Winrate	mb
Chen	Support	8	36.36%	100.00	42.86	2	100.00%	2.0	6	54.55%	6.0
Leshrac	Core Midlane	6	27.27%	96.43	50.00	1	0.00%	1.0	5	80.00%	5.0
Dazzle	Support	2	9.09%	92.86	17.86	1	100.00%	1.0	1	80.00%	1.0
Kunkka	Core Midlane	2	9.09%	89.29	21.43	1	100.00%	1.0	1	80.00%	1.0
Lone Druid	Core Midlane	2	9.09%	85.71	25.00	1	100.00%	1.0	1	75.00%	1.0
Ember Spirit	Core Safelane	2	9.09%	82.14	28.57	1	100.00%	1.0	1	66.67%	1.0
Phantom Lancer	Core Safelane	2	9.09%	78.57	32.14	1	100.00%	1.0	1	60.00%	1.0
Sand King	Core Offlane	2	9.09%	75.00	35.71	1	100.00%	1.0	1	50.00%	1.0
Rubick	Support	2	9.09%	71.43	39.29	1	100.00%	1.0	1	37.50%	1.0
Terrorblade	Core Safelane	1	4.55%	67.86	3.57	1	100.00%	1.0	0	100.00%	0.0
Dark Seer	Core Offlane	1	4.55%	64.29	7.14	1	100.00%	1.0	0	0.00%	0.0
Legion Commander	Core Offlane	1	4.55%	60.71	10.71	1	100.00%	1.0	0	100.00%	0.0
Lich	Support	1	4.55%	57.14	14.29	1	100.00%	1.0	0	0.00%	0.0
Rubick	Core Offlane	4	18.18%	53.57	75.00	2	50.00%	2.0	2	37.50%	2.0
Windranger	Core Midlane	3	13.64%	50.00	46.43	1	100.00%	1.0	2	0.00%	2.0
Slark	Core Safelane	5	22.73%	46.43	92.86	1	0.00%	1.0	4	50.00%	4.0
Abaddon	Core Offlane	4	18.18%	42.86	100.00	1	0.00%	1.0	3	40.00%	3.0
Doom	Support	2	9.09%	39.29	67.86	1	0.00%	1.0	1	71.43%	1.0
Drow Ranger	Core Safelane	2	9.09%	35.71	71.43	1	0.00%	1.0	1	66.67%	1.0
Tiny	Core Midlane	2	9.09%	32.14	78.57	1	0.00%	1.0	1	57.14%	1.0
Venomancer	Core Offlane	2	9.09%	28.57	82.14	1	0.00%	1.0	1	50.00%	1.0
Nature's Prophet	Support	2	9.09%	25.00	85.71	1	0.00%	1.0	1	50.00%	1.0
Crystal Maiden	Support	2	9.09%	21.43	89.29	1	0.00%	1.0	1	14.29%	1.0
Lina	Core Offlane	1	4.55%	17.86	53.57	1	0.00%	1.0	0	100.00%	0.0
Axe	Core Offlane	1	4.55%	14.29	57.14	1	0.00%	1.0	0	0.00%	0.0
Invoker	Core Midlane	1	4.55%	10.71	60.71	1	0.00%	1.0	0	0.00%	0.0
Winter Wyvern	Support	1	4.55%	7.14	64.29	1	0.00%	1.0	0	100.00%	0.0
Alchemist	Core Safelane	2	9.09%	3.57	100.00	1	0.00%	1.0	1	0.00%	1.0