wordlist =
  Import["http://wiki.puzzlers.org/pub/wordlists/unixdict.txt",
   "Words"];
Print["The number of words in unixdict.txt = " <>
  ToString[Length[wordlist]]]
StringMatchQ[#, ___ ~~ "c" ~~ "i" ~~ "e" ~~ ___] & /@ wordlist ;
cie = Count[%, True];
StringMatchQ[#, ___ ~~ "c" ~~ "e" ~~ "i" ~~ ___] & /@ wordlist ;
cei = Count[%, True];
StringMatchQ[#, ___ ~~ "i" ~~ "e" ~~ ___] & /@ wordlist ;
ie = Count[%, True] - cie;
StringMatchQ[#, ___ ~~ "e" ~~ "i" ~~ ___] & /@ wordlist ;
ei = Count[%, True] - cei;
test1 = ie > 2 ei;
Print["The rule \"I before E when not preceded by C\" is " <>
  If[test1, "PLAUSIBLE", "NOT PLAUSIBLE"]]
Print["There were " <> ToString[ie] <> " examples and " <>
  ToString[ei]  <> " counter examples, for a ratio of " <>
  ToString[N[ie/ei]]]
test2 = cei > 2 cie;
Print["The rule \"E before I when preceded by C\" is " <>
  If[test2, "PLAUSIBLE", "NOT PLAUSIBLE"]]
Print["There were " <> ToString[cei] <> " examples and " <>
  ToString[cie]  <> " counter examples, for a ratio of " <>
  ToString[N[cei/cie]]]
Print["Overall the rule is " <>
  If[test1 && test2, "PLAUSIBLE", "NOT PLAUSIBLE" ]]