Which of the following is NOT a method of data analysis?

The correct option is Subjective method.

To understand why this is the correct choice, let's examine the standard methodologies used in data analysis:
1. Qualitative method: This involves analyzing non-numerical data (such as words, images, or behaviors) to understand underlying concepts, opinions, or experiences.
2. Quantitative method: This focuses on testing theories and hypotheses using numerical data and statistical, mathematical, or computational techniques.
3. Mixed method: This integrates both qualitative and quantitative data analysis within a single study to provide a more comprehensive understanding of the research problem.

In contrast, data analysis aims to be systematic, structured, and objective. A "subjective method" is based on personal opinions, interpretations, points of view, and emotions rather than factual, reproducible, and systematic analytical frameworks. Therefore, a purely subjective approach is not recognized as a standard scientific method of data analysis.