def spike_height_experimental(trending_score, x, x_old, time_boost=1.0):
    """
    Compute the size of a trending spike.
    """

    # Magnitude of trending spike
    mag = abs(x - x_old)**0.95

    # Sign of trending spike
    sign = 1.0
    if x < x_old:
        sign = -1.0

    alpha = 0.8
    ell = 100.0
    x_ = max(x, x_old)
    mag *= ell**alpha*(x_ + ell)**(-alpha)

    return time_boost*sign*mag