Practice Free PCED-30-01 Exam Online Questions
What is the formula for calculating the standard deviation of a population?
- A . sqrt(S(x – m)^2 / N)
- B . sqrt(S(x – m)^2 / (N-1))
- C . S(x – m) / N
- D . S(x – m) / (N-1)
What type of plot would be most suitable for comparing the distribution of a numerical variable across different categories?
- A . Scatter plot
- B . Pie chart
- C . Box plot
- D . Bar plot
What is the purpose of a confidence interval in statistical analysis?
- A . To determine the significance level of a hypothesis test
- B . To estimate the range within which the population parameter is likely to fall
- C . To calculate the p-value of a statistical test
- D . To identify outliers in a dataset
Which of the following techniques can be used for data sampling during data acquisition?
- A . Importing entire datasets for analysis
- B . Downsampling to reduce dataset size
- C . Collecting data from multiple sources simultaneously
- D . Upsampling to increase dataset size
What is the purpose of feature engineering in data modeling?
- A . To create new features from existing ones
- B . To visualize data
- C . To evaluate model performance
- D . To clean data
What statistical test is used to compare means between more than two groups or conditions?
- A . Independent samples t-test
- B . Paired t-test
- C . ANOVA
- D . Wilcoxon signed-rank test
Which of the following is a key advantage of using dashboards in data visualization?
- A . Dashboards allow for complex data analysis
- B . Dashboards provide real-time data updates
- C . Dashboards help in creating interactive visualizations
- D . Dashboards simplify the presentation of multiple visualizations in one place
Which of the following is a common approach for data modeling?
- A . Linear regression
- B . K-means clustering
- C . Principal component analysis (PCA)
- D . Random forest
Which of the following Python libraries can be used for creating geospatial visualizations and maps?
- A . Plotly
- B . Matplotlib
- C . Seaborn
- D . Altair
What is the purpose of correlation analysis in statistical analysis?
- A . To compare means of two independent groups
- B . To test the association between categorical variables
- C . To measure the strength and direction of a linear relationship between two continuous variables
- D . To analyze variance among multiple groups