 class Characteristic {
 public:
 	// constructor
-	__device__ __host__ Characteristic(int iter, int id) : current_iter(iter), idata(id);
+	__device__ __host__ Characteristic(int iter) : current_iter(iter);
 	__device__ __host__ virtual ~Characteristic() {}
 
 	// set the state of the random number generator

__constant__ int c_ndata; // # of data points
__constant__ int c_mfeat; // # of measured features per data point
__constant__ int c_pchi; // # of characteristics per data point
__constant__ int c_dim_theta; // # dimension of population parameters

// Function to compute the rank-1 Cholesky update/downdate. Note that this is done in place.

	}

protected:
	// random number generator state for this characteristic
	curandState& state;
	// MCMC sampler parameters
