A time series is a sequentially recorded numerical data points for a given variable arranged in sequential order to track variation.

A. The sum of weights in moving average and polynomial trend is unity,.
B. If the growth rate is constant, the trend is a polynomial (quadratic)
C. Time series data analysis is of three types. Time series, cross-sectional and pooled Data.
D. When a time series is a collection of data for multiple variable and how they vary over a time, Then it is known as multivariate data set.
E. The patterns and behaviour of the data in any time series are based on three components.

Choose the correct answer from the options given below:

C, D only

$\text{Evaluate each statement:}$

$(A)\;\text{False.}$

$\text{Weights sum to unity in moving averages, not in polynomial trend fitting.}$

$(B)\;\text{False.}$

$\text{Constant growth rate implies exponential trend, not quadratic.}$

$(C)\;\text{True.}$

$\text{Data analysis types: time series, cross-sectional, pooled data.}$

$(D)\;\text{True.}$

$\text{Multiple variables observed over time form multivariate time series data.}$

$(E)\;\text{False.}$

$\text{Time series has four components: trend, seasonal, cyclical, irregular.}$

$\text{Correct statements are (C) and (D).}$