1. A test apparatus that tests a device under test, comprising: a vector expanding section that sequentially generates a plurality of test vectors; a predicting section that calculates a predicted value for each test vector by simulating an operation of the device under test, the predicted value indicating a prescribed characteristic value of the device under test to be measured while the device under test is supplied with a test signal corresponding to the test vector; a measuring section that obtains a measured value for each test vector by measuring the prescribed characteristic value of the device under test each time the device under test is supplied with a test vector; and a judging section that judges whether the device under test is defective based on a ratio between the predicted value and the measured value corresponding to each test vector.