* @return This builder (for chaining)
* @see #addChannel(TypedSymbol, Object)
*/
public ScoredIdBuilder addChannel(Symbol symbol, double value) {
Preconditions.checkNotNull(symbol, "symbol cannot be null");
DoubleSymbolValue sv = SymbolValue.of(symbol, value);
Iterators.removeIf(channels.iterator(),
SymbolValue.hasSymbol(sv.getSymbol()));
channels.add(sv);
return this;
}