Golf ball and method of evaluating golf ball

A method of evaluating a golf ball having on its surface a large number of two types or more dimples different in diameter and/or depth, comprising the steps of:

• calculating an EAstdev value of said golf ball;
• and
• estimating, if said EAstdev value is 2 or less, that the uniformity of a dimple arrangement of said golf ball is high and thereby an aerodynamic isotropy of said golf ball is good,
• wherein said EAstdev value is expressed by the following equations:
• 9 EA ⁡ ( α j ) = ∑ i = 1 N ⁢ [ S i × sin ⁢ ⁢ ( θ i ) ] EAstdev = N ⁢ ∑ j = 1 N ⁢ [ EA ⁡ ( α ⁢ ⁢ j ) ] 2 - [ ∑ j = 1 N ⁢ [ EA ⁡ ( α ⁢ ⁢ j ) ] 2 N ⁢ ⁢ ( N - 1 )
• where N is the total number of dimples;
• each of suffixes “i” and “j” is a dimple ID number;
• αj is a rotational axis of a golf ball determined by a straight line connecting the center of the dimple having an ID number “j” to the center of gravity of the golf ball;
• EA (αj) is an aerodynamic index of a dimple arrangement around the rotational axis αj;
• θi is an angle formed between the rotational axis αj of the golf ball and a straight line connecting the center of the dimple having the ID number “i” to the center of gravity of the golf ball;
• and Si is an area of a planar shape formed by a peripheral edge of the dimple having the ID number “i”.