The ROC curve is a visual index of the accuracy of the assay. The further the curve lies above the reference line, the more accurate the test. Here, the curve is difficult to see because it lies close to the vertical axis.

To show more of the detail in the ROC curve, activate the plot by double clicking on it.

In the Chart Editor window, activate the vertical axis by double clicking on it.

Type 0.9 as the minimum displayed value.

Click OK.

In the Chart Editor window, activate the horizontal axis by double clicking on it.

Type 0.1 as the maximum displayed value.

Click OK.

For a numerical summary, see the area under the curve.