related to essential factors like the macro-economic
indicators, financial ratios, and technical indicators
[2,9]. Given the complexity and instability facing
financial markets, there was a need to explore new,
more structured, and systematic models.
In the last decade, an application boom could be
observed when the use of machine learning
algorithms was concerned to analyze financial data or
to identify hidden patterns [4,7]. Amongst these, deep
learning models have been used, for example, Long
Short-Term Memory (LSTM) networks, and are
competent in capturing both the spatial and temporal
expectations that add to the accuracy of the prediction
[5, 10]. Various other studies have been conducted on
the effectiveness of the LSTM network in predicting
stock prices [1, 3]. The researchers have combined
historical price data with lots of indicators to give
insights to investors and traders. Several studies show
that the performance of LSTM models is more
advantageous to conventional other models, such as
autoregressive integrated moving average ARIMA
[3, 6]. Stock price prediction can also be performed
using ARIMA models, which are less accurate than
LSTM models due to their autoregressive and moving
average characteristics [6]. Another predictive
method that has gained popularity in predicting stock
prices is the Support Vector Machine (SVM), based
on the principle of maximizing profits by classifying
data points into two different categories [4]. Besides,
the SVM models for detecting complex patterns and
relationships in financial time series effectively boost
predictive power and robustness [7].
3 METHODOLOGY
This research evaluates the performance of popular
machine learning methods towards stock price
predictions in different scenarios. For analyzing the
capabilities of each method, four distinct datasets are
used namely Adani Ports, ONGC, Tata Motors, and
HDFC [15]. COVID-19 was a time of major changes
which had a major impact on financial markets as
well, keeping the same in mind selected methods are
evaluated on their predictive power on stock datasets
during the COVID-19 period. This study has also
analyzed Short term and long-term datasets to assess
the performance of the selected model.
3.1 Dataset
This research, aims to provide detailed insights into
the selected four datasets from the year 2000 to 2021,
which included vital financial data concerning four
promising organizations in the Indian business world
namely Adani Ports, ONGC, Tata Motors and HDFC.
Table 1. Statistics of selected four datasets
HDFC ONGC
Adani
Ports
Tata
Motors
count 5306 5306 3322 5306
mean 1283.664 491.138 344.20 409.45
std 709.25 385.197 193.04 272.47
Table 1, shows the statistics of the datasets, the
'count' value indicates the total number of data points
available for each stock. In Table 1, 'mean' value
represents the average closing price of the stocks over
the period studied. HDFC has the highest average
closing price at 1283.664, followed by ONGC at
491.138.
3.2 Dataset Pre-Processing
Data preprocessing has to be standardized, lest the
numerical values of different ranges compromise the
result. The range of the closing price value of the four
stocks differs greatly; hence, scaling is one of the
techniques used. This scaling method refers to "min-
max Scaling" technique, which is applied to make
data transformation as expressed using equation (1).
The original data, which in this case is the original
closing price 𝑋, still are retained in their normal form
during this technique. This makes the original
distribution of data adaptable for computational
analysis.
Scaled Value = X
scaled
= X-X
min
/ X
max
-X
min
(1)
By applying the scaling method, we made sure that
the closing prices for each stock were weighted
comparatively with the scaling method, hence making
relative analysis and drawing valid inferences
concerning the trend and pattern of the selected
companies.
3.3 Regression Methods
Long Short-Term Memory (LSTM), autoregressive
integrated moving average (ARIMA), and support
vector machine (SVM) are the other three regression
techniques used for the prediction of stock prices.
• Long Short-Term Memory (LSTM):