Logitraw objective function ignored for xgb.Booster

[Guido Bartoli]

When exporting a Booster model trained with the Logitraw objective function using m2cgen, a sigmoid function is applied to the final score in the resulting C or Python code as if the Logistic objective function had been utilized during training.

#include <math.h>

static float sigmoid(float x) {
    if (x < 0) {
        float z = expf(x);
        return z / (1.0f + z);
    }
    return 1.0f / (1.0f + expf(-x));
}

void predict(uint32_t* x, float* y) {
    // [... boosting rounds omitted ...]

    float v11 = sigmoid(v0 + v1 + v2 + v3 + v4 + v5 + v6 + v7 + v8 + v9 + v10);
    memcpy(y, (float[]){1.0f - v11, v11}, 2 * sizeof(float));
}

In this snippet, the sigmoid() function should not be applied on the final sum, since logitraw uses the raw score output from single trees.

Anyone can confirm this?

Thanks