So, is this a monad?

mapMonad.js

// _* implementations go here. They all return a list of locations.

var MapMonad = function(locations) {
    return {
        fit           : function(map) { return MapMonad(_fit(locations, map)); },
        sprinkle      : function(map) { return MapMonad(_sprinkle(locations, map)); },
        mark          : function(map) { return MapMonad(_mark(locations, map)); },
        hide          : function()    { return MapMonad(_hide(locations)); },
        filter        : function(fn)  { return MapMonad(_filter(fn)); },
        locations     : locations
    }
};

// So, is this a monad ?