Expression error using checkbox control

Question

I'm trying, for the first time, to create an expression that controls a value depending on whether or not a keyed checkbox is on.  This is my code.
x = comp("overlay grain").layer("frame").transform.position;
If (effect("Frame Stutter")("Checkbox") == true)
    value = x + wiggle(25,5);
Else
    value = value + wiggle(25,5);
When I run this, I get the error:
After Effects warning: Function If is undefined
Expression disabled.
Error occurred at line 3.
Comp: 'main'
Layer: 1 ('Date Stamp')
Property: 'Position'
I have been racking my brain over what the problem is.  I have used If/Else statements in the past successfully and I know that there is just something very simple that I am missing.  I have also tried using "== 1" instead of "== true", but I got the same result.
Help please.

Answer 1

I see a few issues here. if and else should not be capitalized. Compare your checkbox to 1, not true. The result of wiggle already includes the value of the property, so value + wiggle() probably won't give you what you expect.
Dan