Terms aggregation giving weird results

Let's consider an aggregation in the Author field to get the statistics of each author name:

curl -XPOST  "http://localhost:9200/news/public/_search?pretty&search_type=count" -d '{
    "aggs" : {
      "authors" : {
        "terms" : {
          "field" : "Author"
        }
      }
    }
}'

By giving search_type=count, we make sure that we receive only the aggregation results and not hits or rather, the top-10 results.

The response we get for this is as follows:

{
  "took" : 5,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "failed" : 0
  },
  "hits" : {
    "total" : 3,
    "max_score" : 0.0,
    "hits" : [ ]
  },
  "aggregations" : {
    "authors" : {
      "doc_count_error_upper_bound" : 0,
      "sum_other_doc_count" : 0,
      "buckets" : [ {
        "key" : "shankar",
        "doc_count" : 3
      }, {
        "key" : "anjali",
        "doc_count" : 2
      }, {
        "key" : "ram",
        "doc_count" : 1...