Online Pearson Example Of Questions ✓ Solved
Online Pearson Example Of Que
Analyze a scatter diagram with specific points and interpret the relationship between two variables based on the pattern of the data points. For the accompanying data set, draw a scatter diagram, compute the correlation coefficient, and determine if there is a linear relationship between x and y, supported by visual and statistical analysis.
Sample Paper For Above instruction
Understanding the relationship between variables is central to statistical analysis. Scatter diagrams and correlation coefficients are fundamental tools used to explore these relationships visually and quantitatively. This paper discusses the interpretation of scatter plots, the computation and significance of correlation coefficients, and their combined role in establishing the presence of linear relationships between variables, using specific examples from Pearson's data sets.
Introduction
The study of relationships between variables involves visual and statistical analyses to determine whether a linear association exists. A scatter diagram offers a visual summary, revealing patterns or trends, while the correlation coefficient provides a numerical measure of the strength and direction of the relationship. Together, these tools facilitate a comprehensive understanding of the data, enabling informed decisions in research and data analysis.
Examining the First Data Set
The first data set presents a series of 12 points with the coordinates: (0.6, 350), (1.2, 350), (2, 350), (3, 350), (4, 350), (6, 350), (7, 300), (7, 270), (8.2, 210), (8.2, 180), (9.8, 20), and (9.8, 50). Observing these points, the initial five points align closely along a horizontal line indicating consistent y-values despite increasing x, suggesting no immediate linear trend in that segment. The subsequent seven points show a decreasing trend with increasing x, forming an approximate straight line that falls from left to right—indicative of a negative linear relationship in this segment.
To determine if the entire set demonstrates a linear relationship, one must consider whether the overall pattern suggests a single linear trend or multiple disparate trends. The first five points do not follow a clear linear pattern with the remaining points. Therefore, the overall data may not exhibit a strong linear relationship, but rather a segmented or mixed pattern. Statistical measures, such as the correlation coefficient, can quantify this relationship, with a coefficient close to -1 indicating a strong negative linear correlation, around zero indicating no linear correlation, and close to +1 indicating a strong positive correlation.
Based on the visual pattern, the initial cluster suggests a non-linear or no clear relationship, while the latter points suggest a negative linear trend. If the correlation coefficient calculation aligns with this observation, it likely would indicate weak to moderate negative correlation in the overall data—less than strong enough to justify a simple linear model for the entire set. Therefore, the data do not fully support a linear relationship across the entire range, but parts of it do.
From the options provided, the best fitting description would be that the data points do not predominantly lie in a straight line, and thus, there is no clear linear relationship overall. However, the pattern that emerges from the latter points suggests a negative trend, but not enough to definitively conclude a strong linear relationship for all points combined.
Analyzing the Second Data Set
The second data set consists of five points: (6,4), (6,8), (7,2), (7,6), and (9,5). When sketching the scatter diagram, the pattern and distribution of these points are critical in determining the relationship between variables.
Visual inspection of these points indicates a possible cluster or scatter without a clear increasing or decreasing trend. Points with the same x-value (such as (6,4) and (6,8)) suggest vertical clustering, implying no strong linear relationship. Others, such as (7,2) and (7,6), show similar behavior at x=7. The point (9,5) doesn't fit into a linear pattern with respect to the other points; it appears isolated in the data cloud.
Calculating the correlation coefficient for these points would likely yield a value close to zero, indicating no significant linear relationship between x and y. The scatter plot analysis supports this conclusion, with no evident trend that suggests a positive or negative linear relationship.
Choosing from the options, the most appropriate depiction would involve points scattered without forming a straight line, supporting the conclusion that there is no significant linear association between the variables.
Conclusion
Visual and statistical analyses are essential for understanding the nature of relationships between variables. In the first data set, a segmented pattern emerges, with part of the data suggesting a negative trend, but overall, the data do not confirm a strong linear relationship. The second set, characterized by scattered points with no clear trend, indicates no linearity. Accurate interpretation of such data necessitates both graphical representation and calculation of correlation coefficients to quantitatively assess relationships.
These techniques are invaluable in research, providing insights that guide modeling choices and further analysis. Recognizing the limitations of visual inspections alone, statisticians rely on correlation measures to make definitive statements about the nature and strength of relationships, which is evident in the examples discussed.
References
- Agresti, A., & Franklin, C. (2017). Statistics: The Art and Science of Learning from Data. Pearson.
- Devore, J. L. (2015). Probability and Statistics for Engineering and the Sciences. Cengage Learning.
- Moore, D. S., Notz, W. I., & Fligner, M. A. (2021). The Basic Practice of Statistics. W. H. Freeman.
- Tabachnick, B. G., & Fidell, L. S. (2019). Using Multivariate Statistics. Pearson.
- Thorndike, R. L., & Hagen, E. P. (2017). Measurement and Evaluation in Psychology and Education. Pearson.
- Field, A. (2018). Discovering Statistics Using R. Sage Publications.
- Upton, G., & Cook, I. (2014). Understanding Statistics. Oxford University Press.
- Hastie, T., Tibshirani, R., & Friedman, J. (2009). The Elements of Statistical Learning. Springer.
- Wasserman, L. (2004). All of Statistics: A Concise Course in Statistical Inference. Springer.
- McNeil, D. R. (2017). Practical Regression and Anova using R. CRC Press.