MMA7361 readings deviate a lot This is what I get using a MMA7361 breakout board (just the IC, no resistors or capacitors). The IC is powered using arduino nano's 3v3 pin.

The x, y, z values are read from analog pins A0, A1, A2. The readings are subtracted with 338.

x   y   z 
-4 -26 44
44 -27 -5
-57 -11 27
-29 -23 22
28 -21 9
-44 3 20
-26 -14 39
26 -32 -8
-17 -12 19
-30 -15 35
4 -26 14
24 -43 49
-58 -19 0
16 -29 24
9 -48 13
-58 -42 12
12 -47 14
-24 -31 9
-46 -31 10
16 -52 1
-43 -21 8
-31 -25 16
37 -18 11
-45 -10 20
-22 -36 16
27 -19 20
-5 -9 1
-59 -10 10
37 -18 30
-53 -18 16
-30 -8 10
54 -19 17
-27 -29 15
-40 -23 -14
-1 -18 19
34 -22 2
-35 -24 41
13 -17 7
-14 -17 21
-39 -14 35
-19 -31 6
62 -9 34
-63 -16 16
-12 -6 23
60 -33 36
-45 -2 34
-18 -15 9


As you can see the x value, when the whole thing is not moving, can range from -59 to +44. This looks very unusual as other people's reading seems to have just +-3 deviations. What might be wrong with my setup?
(just the IC, no resistors or capacitors)
  
  What might be wrong with my setup?


That's easy: You miss the capacitors ;-)
Check figure 5 of the datasheet and try again.