Statistics & Applications

Trends & Data

Medium

applied

Which of the following are examples of irregular trends in a time series?

(A) Decrease in production due to a sudden strike.

(B) The rise in prices before festivals

(C) Unusual rise in income of the printing press due to the announcement of an election.

(D) Fall in crop yield due to floods.

Choose the correct answer from the options given below:

(A), (B) and (D) only

(A), (C) and (D) only

(B), (C) and (D) only

(B) and (C) only

✅ Correct Option: 2

A time series is data collected over time. Irregular trends are unpredictable, random, one-time events that affect the data unexpectedly.

Key characteristics of irregular trends:

Analyzing option (A): Decrease in production due to a sudden strike

Strikes are unpredictable and do not occur regularly.

This is an irregular trend.

Analyzing option (B): The rise in prices before festivals

Festivals occur every year at the same time (Diwali, Christmas, Eid, etc.). This pattern is predictable and recurring.

This is a seasonal variation, not an irregular trend.

Analyzing option (C): Unusual rise in income of the printing press due to the announcement of an election

Election announcements are unpredictable. The word "unusual" indicates this is an irregular occurrence.

This is an irregular trend.

Analyzing option (D): Fall in crop yield due to floods

Floods are natural disasters that are sudden and unexpected. They cannot be predicted reliably.

This is an irregular trend.

Irregular trends are present in options (A), (C), and (D).

The correct answer is the option that includes (A), (C), and (D).

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Solution