Aspects of the disclosure relate to quality control of survey data used to generate and or supplement map information. A device may be walked through an indoor space in order to collect survey data (accelerometer, gyroscope, wireless network identifiers, etc.). The survey data is then transmitted to a server for further processing to identify the path (or the various locations) of the device in the indoor space. The path may be determined by referring to a map of the indoor location and a localization algorithm, for example, a particle filter or least squares optimizer. The path may be compared to other survey data and paths from the same indoor space as well as the map in order to provide an estimate of the quality of the localization produced for the survey data. Low quality survey data may be flagged for further review or used to make changes to the map.