setParameter Problems

Hi, I´m creating a sample operator with balanced data, but when I want to set the parameter PARAMETER_SAMPLE_RATIO_LIST i don´t know how to do it.I want to take all the example that has the label=good  and half of label=bad so the values would be: good-> 1.0 and bad -> 0.5.How should I set this parameter.
My code is:

public ExampleSet randomSampling(ExampleSet ES,String ProcessPath){
        
       try{
                Operator op= OperatorService.createOperator(SamplingOperator.class);
                op.setParameter(SamplingOperator.PARAMETER_SAMPLE, "relative");
                op.setParameter(SamplingOperator.PARAMETER_BALANCE_DATA, "true");
                op.setParameter(SamplingOperator.PARAMETER_SAMPLE_RATIO_LIST, "good, 1.0");
                op.getInputPorts().getPortByIndex(0).receive(ES);
                op.doWork();
                ExampleSet result=null;
                if(op.getOutputPorts().getPortByIndex(0).getAnyDataOrNull() instanceof ExampleSet)
                    result=(ExampleSet) op.getOutputPorts().getPortByIndex(0).getAnyDataOrNull();
                return result;
            }catch(OperatorCreationException | OperatorException e){
                 System.out.println(e);
                return null;
            }
            
        
    }