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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Using Machine Learning to Predict Food Prices in Kazakhstan</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Saya Sapakova</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Askar Sapakov</string-name>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Nurgul Madinesh</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ali Almisreb</string-name>
          <email>a.almisreb@iitu.edu.kz</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Meruyert Dauletbek</string-name>
          <email>m.dauletbek@iitu.edu.kz</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Faculty of Natural Sciences and Engineering, International University of Sarajevo</institution>
          ,
          <country country="BA">Bosnia and Herzegovina</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Information System Department, al-Farabi Kazakh National University</institution>
          ,
          <addr-line>Almaty</addr-line>
          ,
          <country country="KZ">Kazakhstan</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>International Information Technology University</institution>
          ,
          <addr-line>Manas St. 34/1, Almaty, 050000</addr-line>
          ,
          <country country="KZ">Kazakhstan</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Kazakh National Agrarian Research University</institution>
          ,
          <addr-line>Valikhanov St. 137, Almaty, 050000</addr-line>
          ,
          <country country="KZ">Kazakhstan</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>The relevance of using machine learning to predict consumer prices for food in Kazakhstan is due to the need to effectively manage prices and ensure the availability of food products for the population. Machine learning can analyze multiple factors, such as inflation, seasonal fluctuations, and changes in supply and demand, and create accurate forecasts, which is critical in times of economic uncertainty and food price volatility. In this work, we used a machine learning method to predict food prices in Kazakhstan. The main focus was on the application of machine learning methods in this context. We used monthly rural, urban, and mixed-price data from 2005 to 2020 to develop and test the models. The study examines the use of machine learning models such as Decision Tree, Random Forest and Gradient Boosting using a dataset obtained from the World Food Program price database. This helps accurately predict future food prices. We also assessed the accuracy of these models using various metrics such root mean square error (RMSE), root mean square error (MSE), as a mean absolute error (MAE) and coefficient of determination (R2). In our work, we came to the conclusion that the Random Forest model performed best in all measurement metrics. Experimental results confirm that the high accuracy produced by the Random Forest model has (0.99) in predicting future food price values. Machine learning, forecasting, consumer price index, random forest, decision tree, gradient boosting.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>This article explores the utilization of machine learning methods to predict food prices in
Kazakhstan. In the dynamic and variable economic environment associated with agriculture and
global markets, accurate food price forecasts become a key factor for both consumers and
producers. The article provides an overview of modern machine learning methods that can be
successfully applied to analyze food price data, including time series, regression, and neural
networks. Next, we discuss the methodology for collecting and processing data necessary for
training and evaluating models. The study results show that machine learning can significantly
improve the accuracy of food price forecasts in Kazakhstan, which can be useful for making
strategic decisions at both the consumer, business and government levels. The methods and
results presented in the article can be used in practical applications to optimize the processes of
managing food prices and mitigating the impact of economic fluctuations on the population of
Kazakhstan. artificial intelligence (AI) and particularly Machine learning play a substantial role
in the prediction of prices, offering precise and highly reliable tools for scrutinizing and
prognosticating the costs of commodities and services. Below are several ways in which machine
learning and AI are exerting an impact on this procedure:</p>
      <p>0000-0001-6541-6806 (S. Sapakova); 0000-0001-5708-7862 (A. Sapakov); 0000-0001-9376-8489 (N. Madinesh);
0000-0001-7581-5747 (A. Almisreb); 0009-0005-5569-4980 (M. Dauletbek)
© 2023 Copyright for this paper by its authors.</p>
      <p>Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).</p>
      <p>Examination of Extensive Data: Machine learning proficiently assesses substantial
quantities of pricing data, encompassing historical records, supply and demand statistics,
macroeconomic indicators, and more. This aids in the identification of concealed patterns and
trends that can exert an influence on price dynamics.</p>
      <p>Prognostication of Temporal Trends: Machine learning methodologies, such as
convolutional neural networks (CNN) and recurrent neural networks (RNN), are adept at
constructing models for predicting prices grounded on temporal sequences. This is especially
crucial for the anticipation of price fluctuations in financial markets and commodity sectors.</p>
      <p>Sentiment Analysis: AI can scrutinize social media, news outlets, and alternative information
sources to gauge public opinion and sentiments capable of influencing price movements. For
instance, sentiment analysis of social media posts can furnish insights into market reactions in
response to news and occurrences.</p>
      <p>Enhanced Pricing Strategy: Machine learning aids organizations in enhancing pricing
strategies by taking into account a diverse array of considerations, including competitive pricing,
cost structures, seasonal variations, and even individual consumer preferences.</p>
      <p>Risk Mitigation: Machine learning models can be deployed for the evaluation of financial risks
linked to commodity and asset prices. This enables businesses and investors to formulate
effective risk management tactics.</p>
      <sec id="sec-1-1">
        <title>Augmented Accuracy and Velocity of Forecasts: Through the utilization of machine</title>
        <p>learning and AI, it is possible to automate the forecasting process and handle data in real-time,
culminating in forecasts that are not only more precise but also more swiftly generated.</p>
        <p>In summation, machine learning and AI have a substantial impact on augmenting the capacity
to foretell prices, rendering the process more precise and adaptable to the swiftly evolving
landscape of market conditions. This holds profound significance for enterprises, financial
institutions, and governmental entities that rely on dependable price forecasts to inform their
strategic decision-making.</p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>2. Literature review</title>
      <p>
        Nowadays, where agricultural and food markets are becoming increasingly dynamic and subject
to various influences, food price forecasting has become an important tool for farmers, consumers
and governments. The application of machine learning approaches to this task has attracted
increasing attention and research. For instance, in Refs. [
        <xref ref-type="bibr" rid="ref1 ref2">1, 2</xref>
        ], researchers use Vector
Autoregression (VAR) and Nonlinear Autoregressive Distributed Lag (NARDL) techniques to
explore the impact of economic policy uncertainty on food prices. They find that rising economic
policy uncertainty leads to a substantial reduction in prices. Therefore, in line with existing
studies, we anticipate a positive connection between economic policy uncertainty and global food
prices. The US Economic Policy Uncertainty Index is employed as an indicator for economic policy
uncertainty in their empirical analysis. The rapid rise in food prices, particularly burdensome for
the poor in developing countries who allocate for foods approximately half of their income, is
primarily attributed to increased biofuel production in the US and the EU. In [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] identifies this as
the major factor behind rising internationally traded food prices since 2002. Other contributing
factors include a weakened US dollar, higher energy costs in food production, and occasional
droughts. This research aligns with many other studies recognizing biofuels as a significant driver
of food price increases. It raises important policy concerns, as government policies in the EU and
the US incentivized biofuel production, which had a substantial impact on food prices.
Reconsidering these biofuel policies in light of their influence on food prices is essential.
      </p>
      <p>
        The impacts of agricultural output investigated in [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], production material prices, and
production prices on China's food prices using panel data from 26 provinces between 2004 and
2015. The research reveals that the primary driver of food prices is price inertia shock, with
limited influence from agricultural output or price transmission shocks within the vertical chain,
emphasizing the importance of price expectations in shaping food prices. The factors influencing
price changes in international food commodity markets considered in [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. By analyzing various
models, it differentiates between fundamental, conditional, and internal drivers of these changes.
The research shows a growing connection between food, energy, and financial markets,
contributing significantly to observed food price spikes and volatility. Short-term price spikes are
amplified by financial speculation, while medium-term volatility is intensified by fluctuations in
oil prices. In [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] showed that statistical analyses linking agricultural yields to weather fluctuations
indicate that high temperatures are a key factor in predicting outcomes. Climate change is
projected to raise these temperatures, leading to yield reductions. These models have
demonstrated their ability to effectively forecast future results. For example, a model based on
historic US corn and soybean yield data from 1950 to 2011 accurately predicted yields for 2012–
2015, a period marked by higher-than-average temperatures due to climate change. The
implications of declining yields are discussed, with a particular focus on adaptation strategies and
their impact on commodity prices.
      </p>
      <p>Numerous scholars examining food price dynamics in the existing body of research
incorporate a diverse array of factors into their investigations. In recent years, advanced
methodologies such as Autoregressive Distributed Lag (ARDL), causality and cointegration
analysis ( as proposed by Granger and Toda-Yamamoto), Dynamic Conditional Correlation (DCC),
Generalized Method of Moments (GMM), Nonlinear Autoregressive Distributed Lag (NARDL),
Generalized Autoregressive Conditional Heteroscedasticity (GARCH), Panel Data Analysis, and
various regression techniques (including Ordinary Least Squares (OLS) and pooled-OLS), Vector
Autoregression (VAR), and Vector Error Correction Model (VECM) have been employed.</p>
      <p>
        Recent research findings demonstrate the compelling outcomes achieved by employing
ensemble learning algorithms. Ensemble methods endeavor to formulate a collection of
hypotheses and amalgamate them, offering practical solutions to various real-world challenges,
including those pertaining to yield prediction [
        <xref ref-type="bibr" rid="ref7 ref8 ref9">7, 8, 9, 10</xref>
        ]. However, there is a notable scarcity of
research cases that directly compare the predictive performance of econometric models with
machine learning algorithms in this domain. Our research addresses this gap, making a distinctive
contribution to the existing literature by focusing on methodological advancements. As a result,
the outcomes of our study carry significant implications for nations seeking to effectively manage
and stabilize food prices.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. Methods</title>
      <p>3.1. Data</p>
      <p>In this research, we leverage a dataset pertaining to food prices in Kazakhstan, sourced from
the World Food Programme's price database. This extensive database covers a wide array of food
items, including maize, rice, beans, fish, and sugar, across 98 countries and approximately 3000
markets. It undergoes weekly updates, primarily consisting of monthly data spanning from 2005
to 2020.</p>
      <p>As previously discussed, we have employed machine learning methods to achieve precise
forecasting. The selection of appropriate models represents a crucial step in attaining high
prediction accuracy. Within this article, we have opted to utilize the following regression models:
Decision Trees, Random Forest, and Gradient Boosting. Following the implementation of these
models, we assess their accuracy by partitioning the dataset into two segments: a training set and
a testing set.</p>
      <p>Based on empirical analysis, monthly data frequency aligns with the monthly announcements
of global food prices. The study spans from January 1991 to May 2021, encompassing a
substantial timeframe.</p>
      <p>The dataset encompasses 3365 rows and 11 columns, encompassing information on various
aspects such as commodities, pricing, and market dynamics in Figure 2. This dataset was
meticulously gathered from diverse regions within Kazakhstan. To import this dataset, we
harnessed the power of Pandas along with an array of libraries tailored for both visual and
statistical analysis. Subsequently, we subjected the input data, which includes market, category,
product, and unit of measure, to a transformation process. Utilizing Scikit-learn's OneHotEncoder
function, we effectively converted these categorical variables into numerical representations,
thereby assigning numeric values to each of these pertinent factors. Following necessary data
preprocessing, diverse models are deployed and assessed in this study. Model evaluation employs
a data splitting technique where 67% of the data serves as the training set, while the remaining
33% is allocated for testing. The initial phase of the research involves data training, which also
serves as the model-fitting process. Subsequently, the second phase assesses the model's
accuracy.</p>
      <sec id="sec-3-1">
        <title>3.2. Methods</title>
        <p>This section elaborates more on the proposed methods such as Decision Tree, Randon forest,
and Gradient boosting.</p>
      </sec>
      <sec id="sec-3-2">
        <title>Decision tree</title>
        <p>Decision trees (DT), serve as versatile tools applicable to both classification and regression
tasks. These algorithms organize datasets into a tree-like structure consisting of a root node,
intermediate nodes, and leaf nodes. Within this framework, each internal node corresponds to
one of the available input variables, determined through criteria such as information gain for
classification challenges and standard deviation reduction for regression scenarios. The leaves,
on the other hand, signify the ultimate predictions or labels. It's worth noting that random forest
and gradient boosting, two prominent algorithms, are fundamentally rooted in decision tree
principles.</p>
        <p>In the context of this study, we specifically employ the decision tree method for regression
problems. Our approach involves the reduction of variance to guide variable selection at internal
nodes. Initially, we calculate the variance of the root node using a specific equation, and
subsequently, we employ a similar equation to compute the variance of the features, a process
instrumental in constructing the decision tree (1).
where in (1), n is the total number of samples, and µ is the average of the samples in the training
set. After calculating the variance of the root node, the variance of the input variables is calculated
as follows:</p>
        <p>,
  2 = ∑  ( )  2 ,
where in (2), X is the input variable, and c is the different values of this attribute. P(c) is the
probability that c is in attribute X and σс2 is the change in the value of c. The input variable that
has the smallest variance or the largest reduction in variance is selected as the best node, as
shown in the equation below:
This iterative procedure persists until the divergence at the leaf node falls below a specified
threshold, or alternatively, until all input variables have been exhausted. After the construction
of the tree is completed, the evaluation of a new instance is facilitated through an inquiry process
directed at the nodes within the tree structure. Upon arriving at a leaf node, the prediction is
derived from the value associated with that particular leaf.</p>
      </sec>
      <sec id="sec-3-3">
        <title>Random forest</title>
        <p>Random Forest (RF) is a sophisticated form of meta-learning, strategically employing a
multitude of decision trees to tackle classification and regression tasks. In the Random Forest
paradigm, a key feature is the random selection of objects and samples for each tree within the
forest. These individual trees are trained autonomously, contributing to the collective wisdom of
the forest. This widely adopted machine learning algorithm, characterized by its assembly of
multiple decision trees, diverges from conventional methods that simply average the predictions
of these trees. Instead, it harnesses the power of randomness through the selection of training
data points and subsets of objects to create node splits.</p>
        <p>Advantages of RF:
•
•
•
•
•
model.</p>
        <p>Proficiency in handling datasets replete with a profusion of features and categories.
Remarkable resilience to variations in the scaling of feature values.</p>
        <p>Availability of techniques for gauging the significance of individual features within the
Exceptional precision in the classification of novel data points.</p>
        <p>Versatility in
conducting</p>
        <p>measurements across divergent scales, encompassing
numerical, ordinal, and nominal realms.</p>
      </sec>
      <sec id="sec-3-4">
        <title>Disadvantages:</title>
        <p>prodigious.
warrants consideration.</p>
      </sec>
      <sec id="sec-3-5">
        <title>Gradient boosting</title>
        <p>• Requisition of substantial memory resources for model storage, which can be quite
•</p>
        <p>Languid computational speed when dealing with missing data values, a drawback that
Gradient boosting represents the process of elevating the proficiency of less capable learners
into more proficient ones. Typically, the less capable learner takes the form of a decision tree that
exhibits subpar performance in data classification. Each additional tree incorporated into the
boosting scheme is essentially a modified version of the original dataset. Boosting can be
conceptualized as a numerical optimization challenge with the objective of minimizing the loss
function inherent to the model by employing a gradient descent approach when introducing new,
less capable learners.</p>
        <p>In essence, gradient enhancement follows a stepwise, cumulative model-building approach. It
systematically trains multiple models in a sequential and incremental manner. When a new less
capable learner is introduced, the previously incorporated learners remain unaltered within the
model. Importantly, gradient boosting offers the capacity to optimize diverse loss functions that
are characterized by their differentiability.</p>
        <p>0( ) = argmin ∑ =1  (  ,  ),
in the realm of our discourse, γ alludes to the anticipated outcomes, while the term "argmin"
signifies the imperative criterion of assigning to F0(x) the predicted value that minimizes the
summation denoted by Σ.</p>
        <p>The computation of F0(x) entails the differentiation of the summation related to the loss
function, followed by its equating to zero. This operation, in turn, furnishes us with the mean of
the observed values of the dependent variable. This inaugural predictive value assumes the role
of the primary leaf node within the framework of the gradient-boosting algorithm.</p>
        <p>For m=1 to M
For j=1…Jm  
= 


= −
∑ ∈ 
 (  , (  ))
 (  )  ( )=  −1( )
 (  ,   −1( 
) +  )</p>
        <p>for i=1,..,n
F ( ) =   −1( ) +  ∑

 =1    ( ∈   )

(4)
(5)</p>
        <p>In this study, the data set is divided using the specified 67%/33% ratio. Once preprocessing
and data division are complete, models like Decision Tree, Random Forest, and Gradient Boosting
are implemented, and their respective accuracies are evaluated.</p>
        <p>The assessment of algorithm performance was conducted by measuring key metrics, including
mean absolute error (MAE), root mean square error (RMSE), mean square error (MSE), and
coefficient of determination (R2). The algorithms demonstrating minimal errors are indicative of
superior accuracy and are thus deemed preferable. MAE quantifies the cumulative absolute
disparities between actual and predicted variables, while MSE represents the mean of squared
errors. The optimization of the loss function, defined as the sum of squared differences between
observed values (yi) and predicted values (ŷi), is employed to calculate the best-fitting linear
regression line, as depicted in the following equation:
1 
  =1(  −  ̂ )2,</p>
        <p>∑
where, n is the number of observations or data points. yi is the actual value (observed value) for
the i-th observation, ŷi is the predicted value generated by the model for the i-th observation.
A smaller MSE value indicates that the model is better at approximating the data. A high MSE
value suggests that the model is making significant errors in its predictions. MSE is also widely
used in machine learning during model training because it can be minimized during the
parameter optimization process.</p>
      </sec>
      <sec id="sec-3-6">
        <title>RMSE</title>
        <p>The Root Mean Square Error (RMSE) stands as a prevalent metric within the realms of
statistics and machine learning, serving as a pivotal tool for assessing the precision of predictive
models, especially in the domain of regression tasks. RMSE, an offshoot of the Mean Square Error
(MSE), furnishes a quantification of the extent to which a model's predictions align with the
observed empirical data.
where:
n is the number of observations or data points;
yi is the actual value (observed value) for the i-th observation;
ŷi is the predicted value generated by the model for the i-th observation;
Σ represents the summation of squared differences across all data points.</p>
        <p>RMSE serves as a singular metric encapsulating the typical scale of discrepancies between
observed and forecasted values. Diminished RMSE values signify a model with predictions that,
on average, closely align with the real data, implying a superior model fit. Conversely, elevated
RMSE values indicate less precise predictions, signifying an inferior fit to the dataset.</p>
      </sec>
      <sec id="sec-3-7">
        <title>R 2 (the coefficient of determination)</title>
        <p>The coefficient of determination, commonly represented as R-squared (R²), quantifies the
fraction of variance in the dependent variable elucidated by the independent variables within a
statistical model. Its scale spans from 0 to 1, with higher values signifying a more substantial
proportion of the dependent variable's variability being elucidated by the independent variables,
thus suggesting an improved model fit.
where:
SSR is the sum of squared residuals, which represents the sum of the squared differences between
the observed values and the predicted values by the model;
SST is the total sum of squares, which represents the sum of the squared differences between the
observed values and the mean of the dependent variable.</p>
        <p>2 = 1 −</p>
        <p>,
∑(  −  ̂)2,
where yi is the observed value, y^ is the predicted value.</p>
      </sec>
      <sec id="sec-3-8">
        <title>3.3. Analyses of results</title>
        <p>In this study, we have employed a machine learning methodology to predict consumer food
prices in Kazakhstan. Our primary emphasis has been on assessing the effectiveness of machine
learning techniques in this context. Forecasting consumer demand plays a pivotal role in the retail
sector, as it aids in cost reduction, maintaining appropriate inventory levels, optimizing
warehouse utilization, and mitigating out-of-stock issues. Precisely predicting future demand
poses a significant challenge for retailers and wholesalers, owing to abrupt shifts in demand
patterns, limited historical data, emerging trends, and seasonal spikes in demand.</p>
        <p>In our research, we analyzed the performance of three different models on consumer food
products. The results indicate that the Root Mean Square Error (RMSE) values were 0.29 for the
Decision Tree model, 0.27 for Gradient Boosting, and 0.085 for Random Forest. Notably, Random
Forest outperformed the other models, while Decision Trees and Gradient Boosting exhibited
similar performance levels.</p>
        <p>Conclusions on the performance evaluation of the Decision Tree algorithm:
• Mean Absolute Error (MAE) indicates that the difference between actual and predicted
food prices is $0.13;
• Root mean square deviation (RMSE) is 0.29;
• Mean square error (MSE) 0.08;
• The coefficient of determination (R2) is 0.97 – this indicates that the agreement between
real data and the data obtained as a result of using the model is high and the model can be
considered good.</p>
        <p>The following results were obtained for the Random Forest algorithm:
• Mean absolute error (MAE) indicates that the difference between actual and predicted
food prices is $0.04;
• Standard deviation is 0.08;
• The coefficient of determination (R2) is 0.99 – that is, the correspondence of real data
with the data obtained as a result of using the model is high and the model can be considered
excellent.</p>
        <p>Additionally, the R-Square values for all models approached 1, indicating a high degree of
accuracy, with 98% and 99% correspondence between real data and model predictions. This
suggests that our models are quite effective. Further analysis revealed that the Random Forest
model had a mean squared error of 0.085, with a minimal difference of 0.042 between actual and
predicted food prices.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Conclusion</title>
      <p>In this study, we investigated established approaches for predicting sales volumes and opted for
machine learning techniques to construct our model. We identified three machine learning
algorithms, namely random forest, gradient boosting, and decision tree, as the most effective for
sales volume prediction. Our primary criterion for these models was achieving the highest level
of accuracy. Using these selected algorithms, we constructed three distinct models. Employing
key quality assessment metrics such as mean absolute error, standard deviation, and coefficient
of determination, we determined that the boosting algorithm yielded the most precise forecasts
with an impressive accuracy rate of 99%. Furthermore, our research focused on evaluating the
performance of these models in the context of consumer food products. Intriguingly, our findings
and subsequent discussion indicated that the Random Forest model outperformed the others in
terms of accuracy. This discovery holds particular significance for busy decision-makers. In
today's volatile economic landscape, characterized by heightened competition in the trade sector,
organizations are increasingly in need of tools that enable seamless and uninterrupted sales
processes. This, in turn, facilitates more precise allocation of financial resources within the
organization. Anticipating the challenges associated with demand forecasting and how to
effectively address them remains a complex analytical trend in the upcoming year. This
complexity arises from the diverse and ever-evolving desires of consumers. Even top-tier
manufacturers may struggle if they fail to align their production with consumer preferences. As
such, the relevance of machine learning models, featuring a range of algorithms for assessing and
responding to consumer demand, continues to persist. This is especially true for fast-moving
consumer products, such as food or fashion, where real-time forecasting is essential.</p>
    </sec>
    <sec id="sec-5">
      <title>5. References</title>
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