# Fuzzy-Based Time Series Forecasting and Modelling: A Bibliometric Analysis
## 4 Research Outputs
### Performance Analysis  
Performance analysis, which is descriptive in nature, evaluates the contributions of research elements to a given field or topic [36]. Table 1 presents several basic metrics that are especially meaningful for performance analysis [32]. ACC denotes the annual citation count (i.e., citations per years since its publication). Figure 2: Flowchart of the research protocol. The articles gathered from the searching process were published in a total of 46 different journals. To address the second research question, Table 2 summarizes the top 20 journals with the highest number of citations and papers to discover the most used and influential sources. Although Applied Soft Computing with 13 papers, followed by the International Journal of Fuzzy Systems and Soft Computing with nine and seven papers, respectively, can be highlighted as the journals with the largest number of works focused on the topic of this study, many other refereed international journals also contributed to the development of fuzzy-based models for time series forecasting in the period 2017-2021. \begin{table}
\begin{tabular}{l c} \hline \hline
**Metric** & **Value** \\ \hline Publication-related metrics & 118 \\ Total publications & 259 \\ Number of contributing authors & 8 \\ Cole-authored publications & 110 \\ Productivity per year & 23.6 \\ Number of journals & 46 \\ Number of countries & 32 \\ Citation-related metrics & 1701 \\ Total citations & 14.42 \\ Average citations per year & 340.20 \\ Average citations per journal & 36.98 \\ Citation-and-publication-related metrics & \\ Collaboration index & 2.19 \\ Collaboration coefficient & 0.54 \\ Number of cited publications & 105 \\ Proportion of cited publications & 0.89 \\ Citations per cited publication & 16.20 \\ \(h\)-index & 23 \\ \(g\)-index & 35 \\ Papers with ACC \(\geq\) 1, 2, 5, 10, 20 & 101, 79, 40, 15, 3 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Basic metrics for performance analysis. \begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Journal** & **Papers** & **\%Papers** & **Cit \({}^{\ddagger}\)** & **Av.Cit** \\ \hline _Applied Soft Computing_ & 13 & 11.80 & 229 & 16.36 \\ _Int. Journal of Fuzzy Systems_ & 9 & 7.63 & 112 & 12.44 \\ _Int. Journal of Approximate Reasoning_ & 3 & 2.54 & 105 & 35.00 \\ _Applied Energy_ & 2 & 1.69 & 94 & 47.00 \\ _Energy_ & 2 & 1.69 & 87 & 43.50 \\ _Granular Computing_ & 6 & 5.08 & 87 & 14.50 \\ _IEEE Trans. on Fuzzy Systems_ & 6 & 5.08 & 79 & 13.17 \\ _Neurocomputing_ & 3 & 2.54 & 69 & 23.00 \\ _Information Sciences_ & 5 & 4.24 & 56 & 11.20 \\ _Knowledge-Based Systems_ & 4 & 3.39 & 55 & 13.75 \\ _Expert Systems with Applications_ & 2 & 1.69 & 51 & 25.50 \\ _Soft Computing_ & 6 & 5.08 & 47 & 7.83 \\ _Engineering Applications of Artificial Intelligence_ & 5 & 4.24 & 46 & 9.20 \\ _Energies_ & 2 & 1.69 & 44 & 22.00 \\ _Neural Computing and Applications_ & 3 & 2.54 & 44 & 14.67 \\ _Applied Sciences-Based_ & 2 & 1.69 & 42 & 21.00 \\ _Int. Journal Machine Learning and Cybernetics_ & 2 & 1.69 & 39 & 19.50 \\ _Journal of Intelligent \& Fuzzy Systems_ & 5 & 4.24 & 36 & 7.20 \\ _Applied Intelligence_ & 2 & 1.69 & 31 & 15.50 \\ _IEEE Access_ & 4 & 3.39 & 17 & 4.25 \\ \hline \hline \end{tabular} \({}^{\dagger}\) Citations (as of March 2022).  
\end{table} 
Table 2: Analysis of the top 20 journals. The top 20 journals accounted for 80% of the total number of citations. Journals such as _Applied Energy, Energy_ and _International Journal of Approximate Reasoning_ exhibited the highest average number of citations per document (47.00, 43.50 and 35.00, respectively). [PERSON]'s rank correlation coefficient between the number of publications and citations was 0.37396, indicating that the most prolific journals are not always the most influential sources. Figure 3 displays a distribution bar chart with the number of papers published per year, thus allowing us to analyse to what extent the interest in the topic is rising or falling.