Minor modifications

README.md

@@ -130,6 +130,41 @@ TBA
 
 `gem_id`: unique identifier of this entry
 
+**Additional information about the annotation scheme:**
+
+The annotation scores given by an individual annotator are:
+
+4: Good example of paraphrases = Dark green button in the annotation
+tool = The two sentences can be used in the same situation and
+essentially "mean the same thing".
+
+3: Mostly good example of paraphrases = Light green button in the
+annotation tool = It is acceptable to think that the two sentences
+refer to the same thing, although one sentence might be more specific
+than the other one, or there are differences in style, such as polite
+form versus familiar form.
+
+2: Mostly bad example of paraphrases = Yellow button in the annotation
+tool = There is some connection between the sentences that explains
+why they occur together, but one would not really consider them to
+mean the same thing.
+
+1: Bad example of paraphrases = Red button in the annotation tool =
+There is no obvious connection. The sentences mean different things.
+
+If the two annotators fully agreed on the category, the value in the
+`annot_score` field is 4.0, 3.0, 2.0 or 1.0.  If the two annotators
+chose adjacent categories, the value in this field will be 3.5, 2.5 or
+1.5.  For instance, a value of 2.5 means that one annotator gave a
+score of 3 ("mostly good"), indicating a possible paraphrase pair,
+whereas the other annotator scored this as a 2 ("mostly bad"), that
+is, unlikely to be a paraphrase pair.  If the annotators disagreed by
+more than one category, the sentence pair was discarded and won't show
+up in the datasets.
+
+The training sets were not annotated manually. This is indicated by
+the value 0.0 in the `annot_score` field.
+
 ### Data Splits
 
 The data is split into ...