The Editor-in-Chief has retracted this article [1] because validity of the content of this article cannot be verified. This article showed evidence of substantial text overlap (most notably with the articles cited [2-6]), and authorship manipulation. None of the authors responded to correspondence about this retraction.

1.:

Mohammadi K, Shamshirband S, Danesh AS (2015) et al Horizontal global solar radiation estimation using hybrid SVM-firefly and SVM-wavelet algorithms: a case study. Nat Hazards. https://doi.org/10.1007/s11069-015-2047-5

2.:

Shamshirband S, Mohammadi K, Tong CW et al (2016) RETRACTED ARTICLE: A hybrid SVM-FFA method for prediction of monthly mean global solar radiation. Theor Appl Climatol 125:53–65. https://doi.org/10.1007/s00704-015-1482-2

3.:

Mohammadi K, Shamshirband S, Tong CW et al (2015) A new hybrid support vector machine–wavelet transform approach for estimation of horizontal global solar radiation. Energy Conv Manag 92:162–171. https://doi.org/10.1016/j.enconman.2014.12.050

4.:

Shamshirband S, Mohammadi K, Yee PL et al (2015) A comparative evaluation for identifying the suitability of extreme learning machine to predict horizontal global solar radiation. Renew Sustain Energy Rev 52:1031–1042. https://doi.org/10.1016/j.rser.2015.07.173

5.:

Gani A, Mohammadi K, Shamshirband S, et al (2016) A combined method to estimate wind speed distribution based on integrating the support vector machine with firefly algorithm. Environ. Prog. Sustain Energy 35(3):867–875. https://doi.org/10.1002/ep.12262

6.:

Shamshirband S, Mohammadi K, Khorasanizadeh H et al (2016) Estimating the diffuse solar radiation using a coupled support vector machine–wavelet transform model. Renew Sustain Energy Rev 56:428–435 (2016). https://doi.org/10.1016/j.rser.2015.11.055