GUARD: Grading Using Aggregated Ranked Difficulty

The aim is to form an Aggregate List that has the smallest possible disagreement with the Ranking Lists. (This is done with a computer, of course.)

This allows one to get an idea of how difficult problems are with respect to other problems.

For instance, there are a zillion problems listed as 7A on --- with a wide range in difficulty: some easier than those listed as 6C, others harder than some listed as 7B.

The Aggregate List provides a more objective (albeit still subjective) estimate of relative difficulty. (The many, many well-known hitches with quantifying difficulty notwithstanding...)

I mapped ranking to implied grade by selecting grade boundaries that minimised the misclassification from average (mean) grades. (E.g. rank 120, say, is chosen to separate 7A from 7A+ because the total # 7A+s ranked < 120 and 7As ranked >120 is minimised.) Perhaps there is a better way of doing this but the main idea is the ranking order, not the grades.

Here are the results.

hard 6C (23.31) Roof on Fire, Rocklands, [+0.17] AH JS KF
hard 6C (23.43) Creaking Heights, Rocklands, [+0.43] AH CG CH JC
soft 7A (23.51) Zombie Island Massacre, Redhill, [-0.49] CL HR JC
soft 7A (23.55) Demi Lune, Rocklands, [+0.55] AH JS KF SN
soft 7A (23.56) Pienk Gesiggie, Kleinmond, [-0.44] CL HR MS
soft 7A (23.59) Bullet Proof, Rocklands, [-0.25] CL HR JC SS
soft 7A (23.62) Sneak, Rocklands, [+0.62] AH CL JC
soft 7A (23.64) Unicorn Whisper, Topside, [+0.64] JC MS RF
soft 7A (23.67) Purgatory, CBD, [+0.01] AH CL JS JC KF ZD
soft 7A (23.69) Sex Etiquette, Rocklands, [+0.78] AH CL KF
soft 7A (23.72) Two Stroke, Topside, [-0.28] CL HR JC KF SN ZD
soft 7A (23.74) Piglet Power, Topside, [-0.26] CH JC ZD
soft 7A (23.77) The Golden Rail, Rocklands, [+0.57] AH CH CL
soft 7A (23.80) Ludic Fallacy, Topside, [-1.08] CL HR MS
soft 7A (23.81) Mannerheim Roof, Rocklands, [-0.02] AH CL JS KF
fair 7A (23.84) Ryan Was Here, Topside, [-0.16] AH CG CH CL HR JS JC RH
fair 7A (23.87) Olli Dusentrieb, Rocklands, [-0.13] AH CL JC SS
fair 7A (23.91) Orange Heart, Rocklands, [+0.82] AH CG CL JS JC KF SN SS
fair 7A (23.97) Mighty Steel Leg, Topside, [-0.53] CH CL HR JC SS ZD
fair 7A (24.00) Kill the Batman, Topside, [+0.00] AH JS JC KF ZD
fair 7A (24.03) Dark Lord Sharon, Redhill, [+0.03] CL HR JC
fair 7A (24.06) Legz Akimbo, CBD, [+0.06] CH JC KF
fair 7A (24.09) Spartacus, Witzenberg, [+0.09] CH JC MS RF ZD
fair 7A (24.12) Silky Natural, Rocklands, [-0.03] JS JC KF
fair 7A (24.13) Blizzard, Topside, [+0.13] JC KF SS
fair 7A (24.14) Test Tube, Topside, [+0.14] CH JC RF
fair 7A (24.15) Light As Night (Stand Start), Topside, [+0.15] CH JC RF
fair 7A (24.17) Snail Trail, TDA, [+0.17] CH HR SS
hard 7A (24.20) Ginger Ninja, Witzenberg, [+0.20] MS RF RH SS
hard 7A (24.22) Cross Purpose, CBD, [-0.36] CH CL SS
hard 7A (24.24) Sunset Traverse, Rocklands, [+0.24] AH CH JS KF
hard 7A (24.26) The Beast, Topside, [-0.44] CL HR SS
hard 7A (24.28) Esoterrorist, Rocklands, [+0.28] AH CH CL HR JC KF
hard 7A (24.30) The Otter's Pocket, Topside, [-0.45] CH JC MS SS
hard 7A (24.33) Bollo, Topside, [+0.33] CG CH JC
hard 7A (24.35) Sprite, Witzenberg, [+0.35] CH MS RF RH
hard 7A (24.37) John Denver, Rocklands, [+0.26] AH CH JS KF ZD
hard 7A (24.39) Hip Hip Chin Chin, Deadwood, [+0.16] CH CL SS
hard 7A (24.40) Like a Squirrel, Rocklands, [-1.31] AH HR JS
hard 7A (24.42) 7th Subject, The Classroom, [+0.29] HR JC SS
hard 7A (24.44) Scissor Fight, TDA, [+0.31] CL HR JC SS
hard 7A (24.49) Kiesl, Rocklands, [+0.24] AH JS KF
soft 7A+ (24.53) Springbok, Rocklands, [-0.47] AH HR JS SN
soft 7A+ (24.63) Dirty Lies, Rocklands, [-0.83] AH CH JS KF
soft 7A+ (24.68) Doubt and Expectation, Topside, [-1.17] CH CM RF RH
soft 7A+ (24.75) General Awesomeness, Witzenberg, [-0.25] CH MS RF
soft 7A+ (24.79) Planet Telex, Topside, [-1.07] AH JS JC
fair 7A+ (24.85) Riot Police, Redhill, [-0.15] HR JC ZD
fair 7A+ (24.89) Colin the Librarian, Rocklands, [+0.59] CG JC KF ZD
fair 7A+ (24.99) Human Energy, Rocklands, [-0.10] AH CH JS JC KF
fair 7A+ (25.08) Papa Lazarou, CBD, [-0.37] CL HR JC KF SS
hard 7A+ (25.18) Four Singers, Redhill, [+0.18] CL HR JC
hard 7A+ (25.29) Panic Room, Rocklands, [-0.50] AH CL JS JC KF SN SS ZD
hard 7A+ (25.38) Gegen Den Wind, Rocklands, [+0.09] AH CL HR JS KF
hard 7A+ (25.46) Vanity, Rocklands, [+0.46] AH JS JC KF MS SN
soft 7B (25.55) Low Down and Dirty, Topside, [-0.45] CL JC MS SS
soft 7B (25.60) Director's Cunt, Rocklands, [-0.07] AH HR JC
soft 7B (25.70) Secret To Olive's Preserve Cupboard, Rocklands, [-0.30] AH HR JS
soft 7B (25.78) Shrek 2, Topside, [-0.82] AH HR JS JC
fair 7B (25.84) Shark Biscuit, Topside, [-0.16] JC MS RF
fair 7B (25.90) Coke, Witzenberg, [-0.10] CH KF MS RF SS
fair 7B (26.16) Barracuda Rail, Rocklands, [+0.41] AH JS KF
hard 7B (26.24) Minki, Rocklands, [+0.31] AH CH JS JC KF
hard 7B (26.29) Maniac, Rocklands, [+0.29] AH JS KF
hard 7B (26.34) Crazy Legs, Rocklands, [+0.34] AH CH JS KF SN
hard 7B (26.39) Believe It or Not, Topside, [-0.21] CG CL JC
hard 7B (26.47) Poison Dwarf, Rocklands, [+0.47] AH CL HR JS KF
soft 7B+ (26.64) Born Into Struggle, Rocklands, [-0.43] AH HR JS KF
fair 7B+ (26.89) Un Petit Hueco Dans Rocklands, Rocklands, [+0.23] AH JS KF
fair 7B+ (27.11) A Question of Balance, Rocklands, [+1.11] AH JS SN
soft 7C (27.57) Teagarden Roof, Rocklands, [-0.03] AH JS JC MS SN
soft 7C (27.69) Sunset Arete, Rocklands, [-0.22] AH HR JS SN
fair 7C (27.90) Rooi Klavier, Rocklands, [+0.02] AH HR JS JC
fair 7C (28.09) Pandemonium, Redhill, [-0.41] JC RF RH
hard 7C (28.28) Ron Ron Et Caramel, Rocklands, [-0.47] AH CM RF
soft 7C+ (28.62) Weichei, Rocklands, [-0.13] AH JS RF SN
soft 7C+ (28.82) White Mazda Clan, Rocklands, [+0.07] AH JS RF

I have only shown problems that three or more people have ranked. The number in square brackets indicates the upgrade/downgrade relative to mean grade.

(Recall that the ranking method imposes the simple constraint that if a problem is considered harder than another it cannot be given an easier grade.)

Initials indicate who ranked the route: Alan Hills, Clara Grant, Clifford Hakimi, Clinton Martinengo, Cuan Lohrentz, Hermann Rabe, Jimbo Smith, Julia Chen, Keith Forbes, Marijus Smigelskis, Robbie Fraser, Ryan Holl, Scott Noy, Sheldon Smith, Zoe Duby.

p.s. Turns out I'm not totally alone in this thinking:

Comments? Queries?

Route grades