Data Analyst By INDOMITABLE LIMITEDOctober 14, 2025October 24, 2025 Welcome to your Data Analyst Data Analyst Which of the following is a key responsibility of a data analyst? Building neural networks Collecting, cleaning, and interpreting data Managing cloud servers Designing web applications None Data Analyst What does the GROUP BY clause do in SQL? Filters rows Sorts rows alphabetically Deletes duplicate rows Aggregates rows based on a column None Data Analyst What type of data visualization is best for showing the distribution of a single numeric variable? Scatter plot Line chart Pie chart Histogram None Data Analyst Which of the following methods is used to handle missing data? Imputation Duplication Transformation Randomization None Data Analyst In statistics, what does “mean” represent? Average value Minimum value Middle value Most frequent value None Data Analyst Which function in Pandas is used to remove missing values? replace() dropna() clean() fillna() None Data Analyst What is the purpose of a pivot table? To remove duplicates To normalize data To visualize relationships To summarize and reorganize data None Data Analyst Which chart is best for comparing proportions between categories? Box plot Scatter plot Histogram Pie chart None Data Analyst In SQL, which command is used to combine results from two tables? MERGE INTERSECT CONNECT UNION None Data Analyst What is the range in statistics? The difference between the largest and smallest values The total number of values The median of the dataset The most frequent value None Data Analyst What is correlation? Measure of relationship between two variables Measure of central tendency Measure of data dispersion Type of regression None Data Analyst Which value of correlation coefficient indicates the strongest negative relationship? -0.1 0.2 0.8 -0.9 None Data Analyst Which SQL clause is used to filter data after aggregation? ORDER BY HAVING WHERE GROUP BY None Data Analyst What is multicollinearity in regression analysis? Data that contains missing values Independent variables with low variance Variables that are highly correlated with each other Dependent variable with outliers None Data Analyst Which visualization best shows the relationship between two numerical variables? Pie chart Scatter plot Bar chart Heatmap None Data Analyst What does the p-value represent in hypothesis testing? The mean of the data The standard deviation The total number of samples The probability of the null hypothesis being true None Data Analyst Which of the following is an example of categorical data? Age Weight Country Temperature None Data Analyst What is data normalization? Cleaning text data Scaling features to a common range Combining datasets Adding missing values None Data Analyst Which Python library is best for creating interactive dashboards? Seaborn NumPy Plotly Matplotlib None Data Analyst What does R² represent in linear regression? Mean of dependent variable Variance of residuals Goodness of fit Gradient of the slope None Data Analyst Which SQL command is used to update existing records? MODIFY UPDATE REPLACE CHANGE None Data Analyst What is outlier detection used for? Finding missing values Identifying abnormal data points Normalizing data Sorting values None Data Analyst In hypothesis testing, what does the null hypothesis state? There is a relationship between variables Data is normally distributed Variables are independent There is no relationship between variables None Data Analyst What is the main purpose of exploratory data analysis (EDA)? To understand patterns and insights from data To build predictive models To clean data automatically To train AI models None Data Analyst What is time series analysis mainly used for? Classifying images Cleaning text data Predicting future trends based on past data Clustering data points None
