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conscientious procedures for handling, storing and analysing, there requires a

more reliable approach. The continuous efforts made in recent decades in
establishing a widely accepted approach has resulted in this fruitful method

called Chemometrics which involves statistical inference, allowing more
improved probabilistic interpretation. It can help visualise complex analytical
data in a simpler and more convenient manner. As we evolve into the modern

world, the amount of data that is generated everywhere is vast. Almost every
process is computerised and visualised, and there is necessity for the forensic

scientist to understand these complex tools for viewing the collected data more
seamlessly. In simple words chemometrics is the integration of statistics,
mathematics and computational methods to extract relevant chemical

information from complex data obtained during investigation.

2. CHEMOMETRIC METHODS

Techniques in chemometrics varies based on the application on which it is being
used. There are three different methods, Pattern Recognition, which is

subdivided into Unsupervised and Supervised method, Regression Technique
and Experimental Design met

2.1 Pattern Recognition:
2.1.1 Unsupervised Pattern Recognition

This method mainly involves detecting patterns in the datasets of the collected
samples without any predefined labels or outcomes, with the help of algorithms

which largely decreases human error. This method also allows comparative
analysis with a process of projecting the new samples onto the previously

collected samples. Hierarchical Cluster Analysis (HCA) which involves merging
data into large clusters based on special distance and relative similarities,
Principal Component Analysis (PCA) which uses dimensionality reduction

technique to offer visual representation of the data are examples of
Unsupervised Pattern Recognition technique.

2.1.2 Supervised Pattern Recognition
In a supervised method, data used involves labelled data. As the name suggests

it involves human intervention which makes it more reliable and acceptable in
the court of law as there is a proof that the process has been done under

authorised supervision.

VERITAS VOLUME: 3, ISSUE: 2 WRITER: R V ISHITHA REDDY