## 3 Methodology and Details of Data Analysis
### Results and Discussion  
The results from the case studies are as follows:  
* LSSA of the inclination data showed that the tall building (HLKL) has significant periodic movements with 24-h and 12-h periods along the north-south and east-west directions. Another periodic movement with an 8-h period was identified along the east-west direction. As expected, the data from Sensor-I and Sensor-II, mounted on the inner faces of the west and north walls, respectively, showed similar results. * Since 1 mrad = 0.001 mm/m and the height of the building is 54 meters, we can derive the horizontal displacements of the building in mm. Thus, the movement with T = 24 h has 0.024 mrad and 0.013 mrad amplitudes, corresponding to 1.3 mm and 0.7 mm horizontal displacements, respectively, in the north-south and the east-west directions. These amplitudes of displacement are judged to be safe for the building. * In the GPS analysis results, no significant displacement is captured between the first and the second campaigns. However, in the time between _the second and the third campaigns_, in which inclination observations were also performed between these campaigns, a significant change of 1.3 cm was detected in Easting of N101. Additionally, there are significant displacements of 1.1 cm and 1.4 cm in the heights of S101 and N102, respectively. * When the differences in the GPS coordinates between _the first and the third campaigns_ were investigated, significant movements were seen at the centimeter level for every deformation point. In the easting of N102, N101, and S102, the differences are 1.0 cm, 1.3 cm, and 1.2 cm, respectively. In the vertical direction, N101 and S101 moved by 1.0 cm. * In the results of GPS analysis, although the displacements were found to be significant at the chosen confidence level, previous experience with this technique has shown that it would not be realistic to determine the displacements to less than a centimeter. Considering the precision of geodetic GPS, the results obtained can be said to be too optimistic [15,19]. The horizontal displacements revealed from the inclination data analysis also support this supposition. * When the movements of the ISTA geodetic pillar and its host building were investigated using inclination data from the two campaigns, periodic movement was found in both structures with T = 12 h and T = 24 h.
* The horizontal displacements of the host building are 0.30 mm/0.20 mm in 2000 and 0.40 mm/0.20 mm in 2002 along the east-west and north-south directions, respectively. * The horizontal displacements of the pillar are 1.07 mm/0.67 mm in 2000 and 0.71 mm/0.79 mm in 2002 along the east-west and north-south directions, respectively. * The LSSA results on GPS data are consistent with the inclination sensor evaluations. Movements with T = 24 h and T = 12 h to the north and with T = 12 h to the east were confirmed. The 0.50 mm displacement supports the previous findings as well. * Considering that ISTA is a member of a global geodetic network and its position data is broadcasted for used as a reference for precise positioning in geodetic and geophysical applications, the amount of displacement is considered to be safe and can be ignored. Thus, no precaution appears to be required to improve its steadiness. Overall, we can draw the following conclusions :  
1. The repeating T = 24 h movements of the tall building (HLKL), ISTA geodetic pillar, and its host building along the east-west and north-south directions can be interpreted as the natural responses of these structures to the warming and cooling phenomena in a day. 2. However, the harmonics with a period shorter than 24 hours may nevertheless be the consequence of daily periodicity as a result of non-linear response of the structure. The environmental effects under consideration should not have fundamental periods of 12 h and 8 h.
3.