The correct number of clusters in Hierarchical clustering can be determined precisely using approaches
such as silhouette scores (True or False) ✔️✔️False
In K Means clustering, the analyst does not need to determine the number of clusters (K), these are
always derived analytically using the kmeans algorithm. (True or False) ✔️✔️False
One big difference between the unsupervised approaches in this module, and the supervised
approaches in prior modules: Unsupervised models do not have a target variable (Y). This make is
difficult to know when they are "right" or correct. (True or False) ✔️✔️True
What is the significance of defining the population in a research study?
✔️✔️ Defining the population clarifies the group being studied, ensuring that the research findings are
applicable and relevant to the intended audience.
Explain the concept of "mean" and how it is calculated.
✔️✔️ The mean is the average of a data set, calculated by summing all values and dividing by the total
number of observations.
What is a "null hypothesis," and why is it essential in statistical testing?
✔️✔️ A null hypothesis is a statement asserting that there is no effect or relationship; it serves as a
baseline to test against an alternative hypothesis.
How do qualitative data and quantitative data complement each other in research?
, ✔️✔️ Qualitative data provides depth and context to quantitative findings, enriching understanding
and supporting more comprehensive analysis.
What is the purpose of conducting a pilot study before a full research project?
✔️✔️ A pilot study tests the feasibility and design of the research method, identifying potential issues
before the main study is conducted.
Define "descriptive statistics" and its role in data analysis.
✔️✔️ Descriptive statistics summarize and describe the main features of a dataset, providing a clear
overview of its characteristics without making inferences.
How does a decision tree aid in decision-making processes?
✔️✔️ A decision tree visually represents choices and their potential outcomes, facilitating structured
analysis and clearer decision-making.
What does it mean when a data set is "skewed"?
✔️✔️ A skewed data set has an asymmetrical distribution, indicating that values are not evenly
distributed around the mean, affecting interpretation.
What is the importance of data cleaning in the research process?
✔️✔️ Data cleaning ensures accuracy and reliability by identifying and correcting errors or
inconsistencies in the data set before analysis.
How do market surveys contribute to understanding customer preferences?