Cauchy test 4

[staplejw]

Failure in: 6:RoundTrip:7:0:t_cauchy_to_students_t:0

haskell/Tests/TestTools.hs:130
expected:
chiSq_iid = fn n nat:
fn mean real:
fn stdev prob:
q <~ plate _ of n: normal(mean, stdev)
return summate i from 0 to size(q):
((q[i] - mean) * prob2real(1/ stdev)) ^ 2
standardChiSq = fn n nat: chiSq_iid(n, nat2real(0), nat2prob(1))
standardChi = fn n nat:
q <~ standardChiSq(n)
return sqrt(real2prob(q))
nonCentralT = fn n nat:
fn delta prob:
U <~ normal(nat2real(0), nat2prob(1))
X <~ standardChi(n)
return (U + prob2real(delta))
* prob2real(sqrt(nat2prob(n)))
* prob2real(1/ X)
t = fn n nat: nonCentralT(n, nat2prob(0))
t(1)
but got:
U7 <~ normal(+0/1, 1/1)
q305 <~ normal(+0/1, 1/1)
return U7 * prob2real(1/ abs(q305))
Cases: 342 Tried: 293 Errors: 2 Failures: 25

Failure in: 6:RoundTrip:7:0:t_cauchy_to_students_t:1

haskell/Tests/TestTools.hs:130
expected:
chiSq_iid = fn n nat:
fn mean real:
fn stdev prob:
q <~ plate _ of n: normal(mean, stdev)
return summate i from 0 to size(q):
((q[i] - mean) * prob2real(1/ stdev)) ^ 2
standardChiSq = fn n nat: chiSq_iid(n, nat2real(0), nat2prob(1))
standardChi = fn n nat:
q <~ standardChiSq(n)
return sqrt(real2prob(q))
nonCentralT = fn n nat:
fn delta prob:
U <~ normal(nat2real(0), nat2prob(1))
X <~ standardChi(n)
return (U + prob2real(delta))
* prob2real(sqrt(nat2prob(n)))
* prob2real(1/ X)
t = fn n nat: nonCentralT(n, nat2prob(0))
t(1)
but got:
p5 <~ normal(+0/1, 1/1)
p3 <~ normal(+0/1, 1/1)
return p5 / p3
Cases: 342 Tried: 294 Errors: 2 Failures: 26

[mkhattab940]

Done in-lining. Test now fails like this:

### Failure in: 6:RoundTrip:0:2:t_cauchy_to_students_t:1
haskell/Tests/TestTools.hs:130
expected:
U <~ normal(+0/1, 1/1)
X <~ normal(+0/1, 1/1)
return U * prob2real(1/ abs(X))
but got:
p5 <~ normal(+0/1, 1/1)
p3 <~ normal(+0/1, 1/1)
return p5 / p3
Cases: 164  Tried: 89  Errors: 0  Failures: 5
Cases: 164  Tried: 90  Errors: 0  Failures: 5

[JacquesCarette]

Hmmm, why does your expected have an 'abs' but the result doesn't? That is very puzzling.

[JacquesCarette]

I've looked at the question you ask (i.e. what the test is) -- it is your 'expected' which is wrong. What you 'got' is correct.

[JacquesCarette]

Fix the expected to be correct.

[mkhattab940]

Ok fixed