## 3 Statistical Analysis
### Daily Values
#### 3.2.3 Daily Radiation Indices
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c} \hline \hline \multicolumn{11}{c}{**Daily Sunshine Duration (\(S_{d}\), hrs)**} & \multicolumn{11}{c}{**Relative Sunshine Duration (\(\sigma=S_{d}\)/\(S_{bd}\))**} \\ \hline
**Month** & **N** & **Mean** & **StDev** & **CV(\%)** & **Min** & **Q1** & **MedianQ3** & **Max** & **Mean** & **StDev** & **CV(\%)** & **Min** & **Q1** & **MedianQ3** & **Max** \\ \hline
1 & 31 & 5.1 & 2.6 & 51.2 & 0.3 & 3.4 & 4.7 & 7.5 & 9.1 & 0.510 & 0.260 & 51.020 & 0.025 & 0.341 & 0.484 & 0.754 & 0.907 \\
2 & 28 & 7.6 & 2.6 & 34.6 & 0.0 & 6.3 & 8.6 & 9.7 & 10.1 & 0.708 & 0.240 & 33.900 & 0.002 & 0.605 & 0.784 & 0.903 & 0.937 \\
3 & & * & * & * & * & * & * & * & * & * & * & * & * & * & * & * & * \\
4 & 29 & 9.0 & 3.6 & 40.6 & 0.7 & 7.4 & 10.1 & 11.7 & 12.5 & 0.691 & 0.276 & 39.930 & 0.055 & 0.583 & 0.805 & 0.897 & 0.949 \\
5 & 31 & 12.0 & 1.4 & 11.2 & 8.9 & 10.8 & 12.4 & 13.1 & 14.0 & 0.868 & 0.091 & 10.440 & 0.657 & 0.805 & 0.901 & 0.939 & 0.984 \\
6 & 19 & 12.5 & 1.7 & 13.6 & 8.3 & 12.4 & 13.2 & 13.5 & 13.6 & 0.868 & 0.118 & 13.620 & 0.577 & 0.866 & 0.916 & 0.941 & 0.946 \\
7 & 31 & 12.8 & 0.6 & 4.6 & 11.3 & 12.6 & 13.0 & 13.2 & 13.6 & 0.912 & 0.043 & 4.720 & 0.791 & 0.896 & 0.933 & 0.940 & 0.947 \\
8 & 31 & 12.2 & 0.5 & 4.4 & 10.9 & 12.0 & 12.2 & 12.6 & 12.9 & 0.920 & 0.039 & 4.240 & 0.805 & 0.920 & 0.935 & 0.946 & 0.953 \\
9 & 30 & 10.8 & 0.9 & 8.4 & 8.2 & 10.4 & 11.1 & 11.5 & 11.8 & 0.892 & 0.068 & 7.670 & 0.672 & 0.885 & 0.917 & 0.932 & 0.949 \\
10 & 31 & 9.0 & 1.4 & 15.9 & 5.5 & 8.4 & 9.6 & 10.0 & 10.4 & 0.815 & 0.123 & 15.090 & 0.508 & 0.767 & 0.850 & 0.905 & 0.940 \\
11 & 30 & 5.1 & 2.9 & 56.6 & 0.0 & 3.0 & 6.1 & 7.4 & 8.9 & 0.501 & 0.284 & 56.640 & 0.002 & 0.289 & 0.588 & 0.730 & 0.898 \\
12 & 30 & 5.5 & 2.6 & 47.6 & 0.1 & 3.5 & 5.9 & 8.1 & 8.5 & 0.572 & 0.272 & 47.600 & 0.013 & 0.363 & 0.614 & 0.837 & 0.878 \\ \hline
**Year** & 321 & 9.2 & 3.6 & 39.4 & 0.0 & 7.1 & 10.0 & 12.2 & 14.0 & 0.748 & 0.246 & 32.830 & 0.002 & 0.661 & 0.856 & 0.924 & 0.984 \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Descriptive statistics of the daily fraction of diffuse to global radiation (\(K_{D}\)). \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Month** & **N** & **Mean** & **StDev** & **CV(\%)** & **Min** & **Q1** & **Median** & **Q3** & **Max** \\ \hline
1 & 31 & 0.514 & 0.239 & 46.45 & 0.142 & 0.277 & 0.529 & 0.683 & 0.951 \\
2 & 28 & 0.351 & 0.219 & 62.32 & 0.09 & 0.189 & 0.280 & 0.486 & 0.982 \\
3 & 31 & 0.406 & 0.234 & 57.62 & 0.096 & 0.197 & 0.392 & 0.551 & 0.936 \\
4 & 30 & 0.356 & 0.219 & 61.59 & 0.081 & 0.180 & 0.280 & 0.448 & 0.898 \\
5 & 31 & 0.203 & 0.110 & 54.26 & 0.083 & 0.112 & 0.186 & 0.273 & 0.503 \\
6 & 30 & 0.201 & 0.099 & 49.26 & 0.087 & 0.125 & 0.186 & 0.246 & 0.522 \\
7 & 31 & 0.152 & 0.045 & 29.66 & 0.078 & 0.118 & 0.140 & 0.185 & 0.285 \\
8 & 31 & 0.152 The characteristic of these relations is that the coefficients of determination are closed to 0.9. Daily Direct Horizontal Fraction (\(K_{B}\)) and Daily Direct Transmittance (\(K_{BT}\))  
The daily direct horizontal fraction is the ratio of daily direct to the daily global irradiation, while the direct transmittance is the ratio of direct horizontal to the extraterrestrial irradiation. Table 12 presents the descriptive statistics of these indices. \(K_{B}\) ranges from 0.434 in January to 0.781 in July. The daily maximum values exceed 0.75 during the winter months and 0.8 in the rest of the months. \(K_{BT}\) ranges from 0.25 in January to 0.541 in July. Maximum values exceed 0.5 throughout the year.