1. What is a time series?
(A) Randomly ordered data
(B) Data collected over time at regular intervals
(C) Data with no trend
(D) Categorical data
2. Which component represents the long-term movement in a time series?
(A) Seasonal
(B) Cyclical
(C) Irregular
(D) Trend
3. Which component shows repeated patterns within a fixed period?
(A) Trend
(B) Seasonal
(C) Cyclical
(D) Random
4. Which time series component represents random variations?
(A) Trend
(B) Seasonal
(C) Irregular
(D) Cyclical
5. What does stationarity in a time series mean?
(A) Mean and variance change over time
(B) Mean and variance remain constant over time
(C) Data is random
(D) Data contains trend
6. Which test is used to check stationarity?
(A) Chi-square test
(B) ADF (Augmented Dickey-Fuller) test
(C) Z-test
(D) T-test
7. Which model is suitable for stationary time series?
(A) ARMA
(B) ARIMA
(C) SARIMA
(D) LSTM
8. What does the “I” in ARIMA stand for?
(A) Independent
(B) Iterative
(C) Integrated
(D) Inverse
9. Which model handles seasonality in time series?
(A) ARIMA
(B) SARIMA
(C) ARMA
(D) Linear Regression
10. What does autocorrelation measure?
(A) Relationship between two different variables
(B) Relationship of a variable with its past values
(C) Error rate
(D) Trend strength
11. Which plot helps identify autocorrelation?
(A) Histogram
(B) ACF plot
(C) Box plot
(D) Scatter plot
12. What does PACF help determine?
(A) Trend component
(B) Order of AR terms
(C) Seasonal pattern
(D) Order of MA terms
13. Which technique is used to remove trend from a time series?
(A) Differencing
(B) Aggregation
(C) Normalization
(D) Clustering
14. What is white noise in time series?
(A) Stationary series with zero mean and constant variance
(B) Time series with trend
(C) Seasonal data
(D) Cyclic data
15. Which model is best for forecasting time-dependent data?
(A) ARIMA
(B) Decision Tree
(C) K-Means
(D) Naive Bayes
16. What does seasonality refer to?
(A) Random noise
(B) Regular patterns at fixed intervals
(C) Long-term increase
(D) Sudden spikes
17. Which error metric is commonly used in time series forecasting?
(A) Mean Absolute Error
(B) Accuracy
(C) Precision
(D) Recall
18. Which model uses deep learning for time series analysis?
(A) ARIMA
(B) SARIMA
(C) LSTM
(D) ARMA
19. What is the purpose of smoothing in time series?
(A) Remove noise to identify trend
(B) Highlight short-term fluctuations
(C) Increase noise
(D) Change data type
20. Which method is used for smoothing time series data?
(A) Moving average
(B) Linear regression
(C) KNN
(D) Logistic regression