Q.What is a time-series?

The random (irregular) component cannot be predicted.

A time series has four components: trend, seasonal, cyclical and random (irregular). Trend, seasonal and cyclical movements follow patterns and can be estimated, but the random component is caused by chance, unforeseen events (natural cala …

The cyclical component of a time series is shown by the notation $C$.

The four components of a time series are usually written as: Trend $=T$, Seasonal $=S$, Cyclical $=C$, and Random/Irregular $=R$ (or $I$). Thus the cyclical component is denoted by $C$ (as in the addi …

An increase in umbrella sales caused by the monsoon is a seasonal variation, because it recurs at the same period every year — option (c).

The GSEB Class-12 Statistics Time Series chapter identifies four components: trend, seasonal, cyclical and irregular variation.

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In a time series, the independent variable is time, denoted $t$ — option (c).

A time series (GSEB Class-12 Statistics) is a set of observations of a variable arranged in order of time. The observed value $y_t$ changes with time, so:

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A fall in agricultural production due to floods is an unforeseen, non-repeating event — a random (irregular) variation. Option (A).

The components of a time series are trend, seasonal, cyclical and random (irregular). Trend, seasonal and cyclical variations are regular and recurring, whereas variations caused by unpredictable, one-off events such as floods, earthqua …

Short-term variation is produced by the seasonal and irregular (random) components.

A time series has four components: trend, seasonal, cyclical and irregular. Trend and cyclical variations operate over long periods (several years), so they are long-term. Variations that occur within a short period (a year or less) are the: …

A drop in production caused by a strike is a random (irregular) variation — a sudden, unpredictable, non-recurring effect.

Reasoning. The four components of a time series are trend, seasonal, cyclical and random (irregular). A strike is an unforeseeable, one-off event that does n …

A time series is a sequence of numerical observations of a variable arranged in order of time.

Definition. A time series is a collection of observations of a variable taken at successive, usually equally-spaced, points or periods of time and arranged in chronological order — for example, monthly sales, yearly production, or daily temperature. Time is the independent variable, and analysing the series …

The seasonal component produces regular (short-term, periodic) variations — option (c).

A time series has four components: trend (long-term), seasonal, cyclical, and irregular. The seasonal component arises from causes that operate in a fixed, repeating rhythm within a year (weather, festivals, customs), so the fluctuations it causes appear at regular intervals and in a predictable pattern.

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It is the decomposition of an observed time series into its components (trend, seasonal, cyclical, irregular) so that each can be measured and interpreted.

A time series is a set of values of a variable recorded over successive time periods. The observed values are the combined effect of several forces. Analysis of a time series means identifying and isolating these forces — its components:

1. Secular trend — the long-term general movement.
2. Seasonal variation — regular short-term (within-a-year) fluctuations.
3. Cyclical variation — medium-term ups and downs (business cycles).
4. Irregular / random variation — unpredictable, accidental fluctuations. …