# Developing Microservice-Based Applications Using the Silvera Domain-Specific Language
## 3 Silvera
### Silvera Concrete Syntax
#### 3.3.2 Service Registry Declaration
The _median_ value (50%-percentile) for each question is either 4 or 5, as shown in Table 17. The _mode_ value is also either 4 or 5, depending on a question. Median and mode values imply that the data is symmetrically distributed [60]. Low values for _Inter-Quartile Range_ (IQR) indicate that there is a consensus among participants that Silvera satisfies the following DSL quality characteristics: functional suitability, usability, reliability, productivity, extendability, and expressiveness. \begin{table}
\begin{tabular}{l c c c c c} \hline \hline
**Question** & **Strongly** & **Disagree** & **Neutral** & **Agree (\%)** & **Strongly Agree** \\  & **Disagree (\%)** & **(\%)** & **(\%)** & **Agree (\%)** & **Strongly Agree** \\ \hline Q6: The concepts and notation of & & & & & \\ Silvera language are learnable and & 0 & 0 & 0 & 33.33 & 66.67 \\ rememberable. & & & & & \\ \hline Q7: Silvera meets the user’s needs for & & & & & \\ MSA specification. & 0 & 0 & 11.11 & 55.56 & 33.33 \\ \hline Q8: Silvera protects users against & & & & & \\ making errors via built-in validation. & 0 & 0 & 11.11 & 61.11 & 27.78 \\ \hline Q9: Silvera shortens the time needed & & & & & \\ to develop a microservice software & 0 & 0 & 5.56 & 33.33 & 61.11 \\ architecture. & & & & & \\ \hline Q10: Silvera reduces the amount of & & & & & \\ human resources used to develop the & 0 & 5.56 & 11.11 & 66.67 & 16.67 \\ microservice software architectures. & & & & & \\ \hline Q11: Silvera provides one and only & & & & & \\ one good way to express every & 0 & 11.11 & 22.22 & 55.56 & 11.11 \\ concept of interest. & & & & & \\ \hline Q12: Each construct in Silvera is used & & & & & \\ to represent exactly one distinct & 0 & 0 & 11.11 & 77.78 & 11.11 \\ concept in the domain. & & & & & \\ \hline Q13: Silvera does not contain & & & & & \\ conflicting elements. & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 16: _Cont._ \begin{table}
\begin{tabular}{l c c c c c c} \hline \hline
**Question** & **0(\%)** & **25(\%)** & **50(\%)** & **75(\%)** & **100(\%)** & **Mode** & **IQR** \\ \hline Q4: Silvera is appropriate for MSA & 3 & 4 & 4 & 4 & 5 & 4 & 0 \\ specification needs. & & & & & & \\ \hline Q5: Silvera language elements are & 4 & 4.25 & 5 & 5 & 5 & 5 & 0.75 \\ understandable. & & & & & & \\ \hline Q6: The concepts and notation of & & & & & & \\ Silvera language are learnable and & 4 & 4 & 5 & 5 & 5 & 5 & 1 \\ rememberable. & & & & & & \\ \hline Q7: Silvera is appropriate for needs & & & & & & \\ of MSA specification. & & & & & & \\ \hline Q8: Silvera protects users against & 3 & 4 & 4 & 4.75 & 5 & 4 & 0.75 \\ making errors. & & & & & & \\ \hline Q9: Silvera shortens the time needed & & & & & & \\ to develop a microservice software architectures. & & & & & & \\ architectures. & & & & & & \\ \hline Q10: Silvera reduces the amount of & & & & & & \\ human resource used to develop the & & & & & & \\ microservice software architectures. & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 17: Analysis of central tendency and dispersion of the responses (n = 18). Values for _median_ and _mode_ show the central tendency, while _Inter-Quartile Range_ (IQR) shows the dispersion of the responses. #### 5.7.3 Hypothesis Testing

We used R language to perform a one-sample Wilcoxon signed-rank test [64] on our hypotheses. The one-sample Wilcoxon test is a rank-based test that calculates the difference between the observed and default values. We chose this test because the Likert scale data is ordinal and cannot be normally distributed. For each question in the questionnaire, we tested if the test result was greater than the default value of 3. In order to control the study-wide error rate, we used Bonferroni correction. For the Bonferroni correction, we multiplied the raw \(p\)-value by \(n\) to compute the corrected \(p\)-value, where \(n\) is the number of hypothesis tests in the study. In Table 18, we present the results of the test.