Clothing 12 made of a cloth is put on a dummy object 11 that is formed into a human-like shape and made of a material having less reflection of electric wave, in order to form a dummy doll 10. Then, a collision prediction test or inspection by a millimeter wave radar is performed while swaying the clothing 12 by a blower 14. By swaying the clothing 12, the result of the measurement with the use of the millimeter wave radar same as that obtained by using an actual human can be obtained. Further, the clothing 12 may be swayed by vibrating the dummy doll 10 or moving the same, instead of the sending air. A reflection plate may be incorporated into the dummy object 11 to change the reflection state of the reflection plate. According to these configurations, the result of the test or inspection similar to the vehicle collision prediction by the millimeter wave radar for an actual pedestrian can be obtained with the use of the dummy doll.