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author | Louise Crow <louise.crow@gmail.com> | 2013-09-24 09:23:44 +0100 |
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committer | Louise Crow <louise.crow@gmail.com> | 2013-09-24 09:23:44 +0100 |
commit | 7d9b66d1ff31afa8d73ea1a81f4e612e41f89cb0 (patch) | |
tree | 5206d9fbaf8d6af58bdaa35cefdfeb34a88c84ff /spec/lib/confidence_intervals.rb | |
parent | 40a28fa2fe21d752a15c11938791d620dd31d17f (diff) | |
parent | 8e7432be764254e6a50e6a06e77bb93bb5bba9fe (diff) |
Merge branch 'release/0.14' into wdtk
Conflicts:
app/views/request/show.html.erb
Diffstat (limited to 'spec/lib/confidence_intervals.rb')
-rw-r--r-- | spec/lib/confidence_intervals.rb | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/spec/lib/confidence_intervals.rb b/spec/lib/confidence_intervals.rb new file mode 100644 index 000000000..cb8717f3d --- /dev/null +++ b/spec/lib/confidence_intervals.rb @@ -0,0 +1,30 @@ +require 'confidence_intervals' + +describe "ci_bounds" do + + describe "when passed all successes" do + it "should never return a high CI above 1" do + ci = ci_bounds 16, 16, 0.01 + ci[1].should be <= 1 + end + end + + describe "when passed all failures" do + it "should never return a low CI below 0" do + ci = ci_bounds 0, 10, 0.05 + ci[0].should be >= 0 + end + end + + describe "when passed 4 out of 10 successes (with 0.05 power)" do + it "should return the correct Wilson's interval" do + # The expected results here were taken from an online + # calculator: + # http://www.vassarstats.net/prop1.html + ci = ci_bounds 7, 10, 0.05 + ci[0].should be_within(0.001).of(0.3968) + ci[1].should be_within(0.001).of(0.8922) + end + end + +end |