Concept

Have you ever wondered which Steemians are best Curators? ...Unfortunately, SteemPower by itself says nothing. It is however, easy to see who are best Content Creators; just navigate through Tags and Trends...and there you go!

But, what about Curators?

I believe there is not enough attention for them, and, as they are as important -if not more- than Content Creators, a better visibility is well deserved.

CAD is an open-source ranking system developed to portrait and rank Steemit Curators by specific indicators. Although CAD is still a prototype, theoretically the following three different indicators are strong enough to discriminate how good a Curator is.

Community Awareness:

This coefficient measures how much a curator votes different authors in relation to the total voted posts.

Altruism Coefficient:

The more a Curator votes other authors rather than himself, the greater the coefficient.

Diversification Coefficient:

Some Curators might vote very generously other users; however, this coefficient ensures that those who selectively vote with more weight specific accounts get penalized.

Do you still remember Standard Deviation from high school maths lessons? This is exactly what is used here. Although a bit complex to explain with actual numbers, Standard Deviation basically measures how spread the voting is among the different authors.

Formula

The CAD system aims to discriminate among users by three different coefficients.

Which translates into:

Ranking Top25 best Curators

"A" stands for Altruism, "D" for Diversification & "C" for Community Awareness

name	Authors	A	AvgVote%	D (σ)	C	Votes	σ	Index
@pharesim	1710	0,992	94	1,06E-02	0,332	5148	313	297969
@freeyourmind	206	1,000	9958	1,00E-04	0,312	660	611	193249
@acidyo	472	0,963	2097	4,77E-04	0,454	1040	2004	177694
@glitterfart	353	0,990	6057	1,65E-04	0,731	483	3091	132668
@analisa	278	1,000	2304	4,34E-04	0,522	533	782	95501
@skan	186	1,000	2647	3,78E-04	0,809	230	1839	67059
@dunia	706	1,000	7912	1,26E-04	0,503	1403	3119	47368
@anwenbaumeister	388	0,967	4001	2,50E-04	0,736	527	2079	45625
@onceuponatime	69	1,000	9638	1,04E-04	0,335	206	1639	44770
@fuzzyvest	151	1,000	4995	2,00E-04	0,314	481	3553	44729
@dan	46	1,000	1108	9,02E-04	0,780	59	1990	42890
@thisvsthis	166	1,000	750	1,33E-03	0,348	477	884	42815
@cervantes	198	0,987	2320	4,31E-04	0,371	533	1456	42046
@kushed	547	1,000	3471	2,88E-04	0,425	1287	2862	38875
@xaero1	194	0,998	5641	1,77E-04	0,649	299	3469	33013
@shaka	173	0,998	3169	3,16E-04	0,579	299	2649	31656
@slowwalker	452	0,991	1695	5,90E-04	0,352	1283	2522	31357
@steemed	24	1,000	9474	1,06E-04	0,113	212	1701	31335
@fyrstikken	591	0,992	1373	7,28E-04	0,713	829	3266	30045
@transisto	106	1,000	7210	1,39E-04	0,442	240	4834	26041
@steempower	129	1,000	8992	1,11E-04	0,510	253	2090	25245
@s4s	390	1,000	8558	1,17E-04	0,589	662	2993	24384
@ioc	118	1,000	6688	1,50E-04	0,494	239	3868	19997
@fminerten	277	1,000	2911	3,43E-04	0,247	1120	4031	19244
@steempty	281	1,000	3006	3,33E-04	0,247	1137	4085	19118

Congratulations to the Top 25 Curators by CAD Ranking System!!

Data Conditions

• Minimum Total Weight: 10^7
• Date: after HF19
• Only considering Posts with payouts greater than 20BSD

Code & Developers Support

Javascript query to SteemData server. Thanks @Furion for the great work!
Feel free to suggest changes or improvements!

db.Posts.aggregate([

{$match :{"total_payout_value.amount":{$gt:20},"created":{$gte: new ISODate("2017-06-20T12:27:12.000Z")}}
},
{$unwind : "$active_votes"},

{
    $project:{
        areEqual: {$eq:["$active_votes.voter","$author"]},
        author:"$author",
        voter: "$active_votes.voter",
        weight: "$active_votes.weight",
        percent: "$active_votes.percent"
    }
},
{
    $group:{
        _id: {voter:"$voter"},            
        total_weight: {$sum:"$weight"},
        authors:{$addToSet:"$author"},
        total_curated_weight: {$sum: 
            {$cond:[{$eq:["$autor","$votante"]},null,"$weight"]}},
        avg_percent:{$avg:"$percent"},
        avg_weight:{$avg:"$weight"},
        max_weight:{$max:"$weight"},
        stdDev:{ $stdDevPop:"$percent"},
        count: { $sum: 1}  
        
    }}, 
    
{
     $match:{
         total_weight:{$gt:100000000}
     }
},
       
{
    $project:{
        _id:0,
        name:"$_id.votante",
        UniqueVotedAuthors:{$size:"$authors"},
        Altruism: {$cond:[{$eq:["$total_weight",0]},null,
            {$divide:["$total_curated_weight","$total_weight"]}]},          
        Total_curated_weight: "$total_curated_weight",
        Total_weight: "$total_weight",
        AvgVotepercent:{$trunc:"$avg_percent"},
        diversification:{$abs:{$cond:[{$eq:["$stdDev",0]},null,
            {$divide:[1,"$avg_percent"]}]}},
        CommunityAwareness:{$cond:[{$eq:["$count",0]},null,
            {$divide:[{$size:"$authors"},"$count"]}]},
        Count:"$count",
        VoteStdDeviation:{$trunc:"$stdDev"},
        CAD_Index: {$trunc:{$multiply:["$total_curated_weight",
            {$cond:[{$eq:["$stdDev",0]},null,
            {$divide:[1,"$stdDev"]}]},
            {$cond:[{$eq:["$count",0]},null,
            {$divide:[{$size:"$authors"},"$count"]}]}]}}
    }
},
{
    $match:{
        diversification:{$ne:null}
    }
},
{$limit:35},
{$sort:{"CAD_Index":-1}}
    
]
).toArray()

Image sources:
http://www.npr.org/tags/131336520/altruism
https://blogs.cfainstitute.org/investor/2015/05/21/the-diversification-dividend/
http://www.warollers.com/community-awareness.html