_unbinds: function () {
    this._dataviewModel.off('change:bins', this._onChangeBins, this);
    this.model.off('change:zoomed', this._onChangeZoomed, this);
    this.model.off('change:zoom_enabled', this._onChangeZoomEnabled, this);
    this.model.off('change:filter_enabled', this._onChangeFilterEnabled, this);