Generate Probabilities around a Numpad
CJam, 27 bytes

12369874s_$\_r#m&lt;f{#4-z)0S}


Try it online in the CJam interpreter.

Idea

If we go through the digits around 5 in counterclockwise fashion, we obtain the string 12369874 or any of its rotations (depending on the starting point).

After rotating this string so that the input digit n is at the leftmost position, the digits in the rotated string have the following probabilities:

50 40 30 20 10 20 30 40


If we consider the indexes of these digits, which are

 0  1  2  3  4  5  6  7


subtract 4 from each to yield

-4 -3 -2 -1  0  1  2  3


and take absolute values to get

 4  3  2  1  0  1  2  3


we only have to add 1 and append a 0 to get the desired probabilities.

Code

12369874s                   e# Push "12369874".
         _$                 e# Push a sorted copy, i.e., "12346789".
           \                e# Swap it with the unsorted original.
            _r#             e# Find the index of the input in an unsorted copy.
               m&lt;           e# Rotate the unsorted original that many units left.
                 f{       } e# For each character C in "12346789":
                            e#   Push the rotated string.
                   #        e#   Find the index of C.
                    4-      e#   Subtract 4.
                      z     e#   Compute the absolute value.
                       )    e#   Add 1.
                        0S  e#   Push a 0 and a space.