This is a perennial problem where you have used two or more references with Anderson and the style is set up to “dis-ambugate” them. If all the Anderson authored papers are the same Anderson, you should copy one of the name and replace the others with it, as subtle changes can have this effect. If there are two different Anderson’s then the behaviour is the correct behavior according to most publishers. If you don’t want it to disambugate these citations, you need to change the output style settings, which again I emphasize is not the accepted way to reference these for most style guidelines).
in Endnote
'Edit>Output Styles>Edit ‘stylename’ and in “citations” section deselect ‘use initials only for primary authors with the same name’.
Save as to a output style name- (“stylename-without-disambugation”) and then go into the word document and either on the ribbon (word2007/2010) or run the format bibliography tool in word and select the new output style.