Intership Body
Intership Body
INTRODUCTION TO PYTHON
1.1 PYTHON
Integer int: Represents whole numbers, both positive and negative, without a fractional
component. e.g: 10, -5.
Float float: Represents numbers that contain decimal points or fractions. e.g: 3.14, -
0.75.
String str: Represents a sequence of characters enclosed in single, –double, or triple
quotes. e.g: "Python", 'Hello World'.
Boolean bool: Represents logical values, either True or False.
List list: An ordered, mutable collection of items, which can be of different data types.
e.g: [1, "apple", 3.5].
1
Tuple tuple: An ordered, immutable collection of items. e.g: (1, 2, "banana").
Set set: An unordered collection of unique elements. e.g: {1, 2, 3, "apple"}.
Dictionary dict: A collection of key-value pairs, where each key is associated with a
specific value. e.g: {"name": "Alice", "age": 25}.
2. else Statement: Executes a block of code if the condition in the if statement is false.
Ex:
x=3
if x > 5:
print("x is greater than 5")
else:
print("x is not greater than 5")
Ex:
x=5
if x > 5:
print("x is greater than 5")
elif x == 5:
print("x is equal to 5")
Ex:
x=10
if x>5:
if x<15:
print(“Between 5 and 15”)
1. for Loop: Iterates over a sequence (such as a list, tuple, or string) and executes a block of
code for each item in the sequence.
Ex:
fruits = ["apple", "banana", "cherry"]
for fruit in fruits:
print(fruit)
2. while Loop: Repeatedly executes a block of code as long as a specified condition is True.
Ex:
x=0
2
while x < 5:
print(x)
x += 1
3. break Statement: Exits the loop prematurely when a certain condition is met.
Ex:
for i in range(5):
if i == 3:
break
print(i)
4. continue Statement: Skips the current iteration and moves to the next iteration in the loop.
Ex:
for i in range(5):
if i == 2:
continue
print(i)
Functions are reusable blocks of code that perform a specific task. They allow for
code modularization, making programs easier to read, maintain, and debug.
A function in Python is defined using the def keyword, followed by the function
name and parentheses containing optional parameters.
Syntax:
def function_name(parameters):
# Function body
# Optional return statement
Ex:
3
2. OOPS IN PYTHON
Python is an object-oriented programming (OOP) language that allows for the creation and
utilization of classes and objects. The major principles of object-oriented programming in
Python include the following:
1. Object:
An object is an entity that has a state (attributes) and behavior (methods). Objects can be
physical (e.g., a mouse, keyboard) or logical (e.g., a user account). In Python, everything is
an object, and all objects have associated attributes and methods. For instance, functions
have a built-in attribute __doc__, which returns the docstring defined in the function source
code.
2. Class:
A class is a blueprint for creating objects. It defines a set of attributes and methods that
the created objects (instances) will have. For example, an Employee class may contain
attributes such as email, name, age, and salary.
Syntax:
class ClassName:
attribute = value
def method_name(self):
# Method body
3. Method:
A method is a function that is associated with an object. In Python, methods are not
unique to class instances; any object type can have methods.
4. Inheritance:
Inheritance is a feature of OOP that allows one class (the derived class or child class) to
inherit the properties and behaviors of another class (the base class or parent class). This
promotes code reusability and reduces redundancy.
Example:
class Parent:
def greet(self):
print("Hello from Parent")
class Child(Parent):
def greet_child(self):
print("Hello from Child")
5. Polymorphism:
Polymorphism allows methods to perform different functions based on the object that is
calling them. It enables a single interface to be used for different underlying forms (data
4
types). For instance, a method named talk can have different implementations for different
animal classes.
Example:
class Animal:
def talk(self):
pass
class Dog(Animal):
def talk(self):
return "Bark"
class Cat(Animal):
def talk(self):
return "Meow"
6. Encapsulation:
Encapsulation is a mechanism that restricts access to certain components of an object
and bundles the data (attributes) and methods (functions) that operate on the data within a
single unit. This can be implemented using private variables and getter/setter methods to
control access.
Example:
class Account:
def get_balance(self):
return self.__balance
5
3. NUMPY & PANDAS
3.1 NUMPY
NumPy is a powerful library for numerical computing in Python, providing support for
large, multi-dimensional arrays and matrices, along with a collection of mathematical functions
to operate on these arrays.
3.1.1 ARRAY
An array is a central data structure in NumPy, allowing for efficient storage and
manipulation of numerical data. It is a grid of values, all of the same type, indexed by a tuple of
non-negative integers. The number of dimensions is called the rank of the array.
NumPy gives you an enormous range of fast and efficient numerically-related options.
While a Python list can contain different data types within a single list, all of the elements in a
NumPy array should be homogenous. The mathematical operations that are meant to be
performed on arrays wouldn't be possible if the arrays weren't homogenous.
Why NumPy?
NumPy arrays are faster and more compact than Python lists. An array consumes less
memory and is far more convenient to use. NumPy uses much less memory to store data and
it provides a mechanism of specifying the data types, which allows the code to be optimized
even further.
import numpy as np
# Creating a 1D array
array_1d = np.array([1, 2, 3, 4, 5])
# Sorting an array
sorted_array = np.sort(array_1d)
6
Resizing an Array:
You can change the shape of an array using the reshape() method.
# Resizing an array
reshaped_array = np.reshape(array_1d, (5, 1)) # Reshaping to 5 rows and 1 column
Indexing:
You can access elements of a NumPy array using indexing.
# Indexing an array
element = array_1d[2] # Accesses the element at index 2
Slicing:
Slicing allows you to access a range of elements in an array.
# Slicing an array
slice_array = array_1d[1:4] # Gets elements from index 1 to 3
Broadcasting:
Broadcasting refers to the ability of NumPy to perform operations on arrays of different shapes.
For instance, you can add a scalar to an array.
# Broadcasting example
array_broadcast = array_1d + 5 # Adds 5 to each element in the array
# Creating a 2D array
array_2d = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
# Accessing an element
element = array_2d[1, 2] # Accesses the element in the second row and third column
print("Element at (1, 2):", element) # Output: 6
7
3.2 PANDAS
Pandas is a powerful Python library used for data manipulation and analysis,
especially in structured data environments. It provides versatile data structures to efficiently
work with large datasets.
import pandas as pd
1. Series: A one-dimensional labeled array, similar to a list, where each element has an
associated index.
2. DataFrame: A two-dimensional, tabular data structure with labeled axes (rows and
columns), similar to a table in relational databases.
3. Panel: A three-dimensional container for data, though less commonly used and largely
replaced by multi-dimensional arrays in `NumPy`.
3.2.3 DATAFRAME
A `DataFrame` is the primary data structure in Pandas, used to store and manipulate
tabular data.
df = pd.read_csv('file.csv')
print(df.head()) # Displays the first 5 rows
# Sorting by a column
sorted_df = df.sort_values(by='Age')
8
3.2.7 GROUPING AND CONCATENATION
Pandas allows grouping data for aggregation and concatenating DataFrames.
9
4. INTRODUCTION TO MACHINE LEARNING
Machine Learning (ML) is a branch of artificial intelligence (AI) that creates algorithms that
learn from data and make predictions or decisions. Rather than being manually programmed for
specific tasks, ML models find patterns in data and improve automatically with experience. This
ability makes machine learning useful for many applications, including data analysis and
automating decisions.
1. Data Collection
The first step involves gathering and preparing data from different sources. The quality and
quantity of data significantly influence model performance.
2. Data Preprocessing
The data is cleaned and transformed to prepare it for the model. This includes handling missing
values, normalizing features, and encoding categorical variables.
3. Model Building
A machine learning algorithm is selected and trained on the prepared data to learn the underlying
patterns.
4. Model Evaluation
The model's performance is assessed using metrics like accuracy, precision, recall, and mean
squared error, often with a validation dataset.
5. Model Deployment
Once the model is trained and evaluated, it is deployed for real-time predictions or integrated into
applications for decision-making.
10
Example Algorithms: K-Means Clustering, Hierarchical Clustering, Principal Component
Analysis (PCA).
3. Semi-Supervised_Learning
Semi-supervised learning is a hybrid approach where the model is trained on a small amount
of labeled data along with a large amount of unlabeled data. This technique helps when
labeling data is costly or time-consuming.
4. Reinforcement_Learning
In reinforcement learning, the model learns through trial and error by interacting with an
environment and receiving feedback in the form of rewards or penalties.
Linear regression is a statistical technique used to model the relationship between one or
more independent variables and a dependent variable by fitting a linear equation to observed data.
It is widely used in predictive analytics, machine learning, and data science to understand and
predict continuous outcomes. The primary goal of linear regression is to find the best-fitting line
that minimizes the difference between predicted and actual values.
Simple linear regression is the most basic form of linear regression where we model the
relationship between a single independent variable (X) and a dependent variable (Y). The
relationship between the two is represented by the equation:
Y = β0 + β 1 X + ϵ
11
Where:
Simple linear regression is useful when there is only one predictor variable, and the relationship
between the variables is assumed to be linear.
Multiple linear regression extends simple linear regression by incorporating more than one
independent variable to predict the dependent variable. The equation for multiple linear regression
is:
Y = β0 + β1 X1+ β2 X2 +….+ βn Xn + ϵ
Where:
Multiple linear regression helps in modeling more complex relationships between the
dependent variable and multiple predictors, providing more accurate predictions than simple linear
regression when multiple factors are involved.
To evaluate the performance of a linear regression model, several metrics are commonly used:
1. Mean Squared Error (MSE): The average squared difference between the observed and
predicted values. Lower values indicate better model performance.
i=1
1
MSE= ∑ ¿¿
n n
2. Root Mean Squared Error (RMSE): The square root of MSE, providing an interpretable
error metric in the same units as the dependent variable.
RMSE=√ MSE
3. R-squared (R²): Represents the proportion of variance in the dependent variable that is
explained by the independent variables. Values range from 0 to 1, with higher values
indicating a better fit
12
4. Adjusted R-squared: Similar to R², but adjusted for the number of predictors in the model,
preventing overfitting when using multiple independent variables.
Each of these metrics provides insights into how well the linear regression model fits the data and
how accurately it predicts outcomes.
Logistic regression is a statistical method used to model the relationship between one or
more independent variables and a categorical dependent variable. Unlike linear regression, logistic
regression is used when the dependent variable is binary or categorical. It estimates the probability
that a given input belongs to a certain category by fitting the data to a logistic curve. The output of
logistic regression is a probability between 0 and 1, which can then be used to classify observations.
Binary logistic regression is the simplest form of logistic regression where the dependent
variable has two possible outcomes (e.g., 0 or 1, yes or no, true or false). The logistic regression
model for binary outcomes can be written as:
Where:
The logistic function transforms the linear equation into a value between 0 and 1,
representing the probability of a certain class.
Multinomial logistic regression is used when the dependent variable has more than two
categories. Unlike binary logistic regression, which predicts probabilities for two classes,
multinomial logistic regression predicts probabilities for multiple classes (e.g., A, B, C). Each class
has its own logistic function, and the probability of an outcome belonging to a particular class is
calculated based on a set of logistic functions. The model is represented as:
Where pk is the probability of class k and p1 is the probability of a reference class. This
model is widely used in scenarios like predicting customer choices or categorizing text into multiple
classes.
13
Several metrics are used to evaluate the performance of a logistic regression model,
especially in classification problems:
1. Accuracy: The proportion of correctly classified observations. It is a basic measure but may
not be useful in cases of imbalanced datasets.
2. Precision: The ratio of correctly predicted positive observations to the total predicted
positives. It is useful when the cost of false positives is high.
3. Recall (Sensitivity): The ratio of correctly predicted positive observations to all actual
positives. It is crucial when missing positive cases (false negatives) is more critical.
4. F1 Score: The harmonic mean of precision and recall. It balances the trade-off between
precision and recall and is useful when both false positives and false negatives are costly.
These metrics help assess how well the logistic regression model performs in classification tasks.
Decision trees are a popular supervised machine learning method used for classification and
regression tasks. They work by recursively splitting the data into subsets based on the value of input
features, resulting in a tree-like structure of decisions. Each internal node in the tree represents a
decision based on a feature, each branch represents the outcome of a decision, and each leaf node
represents the final classification or regression result.
Decision trees are intuitive, easy to interpret, and can handle both numerical and categorical
data, making them useful for a wide range of problems.
Constructing a decision tree involves selecting the feature that best separates the data at each
step, typically based on a criterion like information gain or Gini impurity. The tree is built
14
recursively by splitting the dataset until all data points in a subset belong to the same class (for
classification) or until a stopping condition is reached (for regression).
1. Select the Best Feature: Choose the feature that provides the most significant separation
between data points using criteria like information gain or Gini index.
2. Create Decision Nodes: Split the dataset into smaller subsets based on the selected feature.
3. Repeat the Process: Recursively apply the same process to the resulting subsets.
4. Stopping Condition: Stop splitting when a certain condition is met (e.g., maximum depth,
all samples in a node belong to the same class).
Several algorithms are used to construct decision trees, the most common being:
1. ID3 (Iterative Dichotomiser 3): This algorithm uses information gain based on entropy to
select the best feature for splitting at each node. It continues building the tree until all
attributes are exhausted or the data is perfectly classified.
2. CART (Classification and Regression Trees): CART is used for both classification and
regression tasks. It splits the data using the Gini impurity for classification or the least
squared deviation for regression. Unlike ID3, CART builds binary trees where each split
produces exactly two branches.
3. C4.5: An extension of ID3, C4.5 handles both categorical and continuous features and uses
a concept of gain ratio (a normalized version of information gain) to split the nodes. It can
handle missing values and allows pruning after tree construction.
Evaluating a decision tree model involves several metrics depending on whether the task is
classification or regression:
4.6.4 PRUNING
Pruning is a crucial step in decision tree optimization that helps reduce overfitting by
removing sections of the tree that are not significant. There are two main types of pruning:
1. Pre-pruning (Early Stopping): Stops the tree construction early, based on predefined
conditions like maximum depth, minimum samples per leaf, or maximum number of nodes.
2. Post-pruning: Involves growing the full tree first and then removing the least important
branches. Post-pruning techniques like cost-complexity pruning use a validation set to prune
branches that do not improve performance.
15
Pruning enhances the generalization ability of the model by reducing the complexity of the
tree, preventing overfitting to the training data.
K-Nearest Neighbors (KNN) is a simple, yet powerful, supervised learning algorithm used
for both classification and regression tasks. It is based on the idea that data points with similar
features tend to be near each other. The KNN algorithm works by identifying the "K" nearest
neighbors to a new data point and classifying it based on the majority label (for classification) or
averaging the labels (for regression). KNN is a non-parametric and lazy learning algorithm,
meaning it makes no prior assumptions about the data distribution and does not learn a model until
predictions are required.
1. Choose the value of K: Select the number of nearest neighbors (K). A smaller K can lead to
overfitting, while a larger K may smooth out the decision boundary but risk underfitting.
2. Calculate the Distance: For a new data point, calculate the distance to all training data
points using a distance metric such as Euclidean distance (most common), Manhattan
distance, or Minkowski distance.
3. Identify Neighbors: Select the K nearest neighbors (those with the smallest distances).
4. Voting or Averaging:
Classification: Assign the new data point to the class that is most common
among its K neighbors (majority vote).
Regression: Calculate the average of the values of the K neighbors to predict the
output.
5. Predict the Label: Return the predicted class label or continuous value.
16
Fig 1: K-NN Procedure
For prediction, given a test sample, KNN computes the distance from the test sample to all
training samples, selects the K closest samples, and determines the output based on the majority
or average of those neighbors. While this process is simple, it can become computationally
expensive when the dataset is large, as KNN must compare the test sample to every training
sample.
1. Pattern Recognition: Used to classify images, handwriting, and speech, as KNN can
identify patterns based on similarity.
2. Recommendation Systems: By comparing user preferences and recommending products,
movies, or services based on the preferences of similar users.
3. Medical Diagnosis: Applied in medical fields to predict diseases or classify patient
conditions based on similarities in medical records or symptoms.
4. Anomaly Detection: Detecting unusual patterns in data for fraud detection, network
security, or fault detection in machinery by finding data points that do not have enough
neighbors close by.
5. Text Classification: Applied in natural language processing (NLP) for spam detection,
sentiment analysis, and categorizing documents.
5.2 CORRELATION
Correlation is a statistical measure that describes the strength and direction of a relationship
between two variables. It quantifies how changes in one variable are associated with changes in
another. A correlation coefficient ranges from -1 to 1, where:
17
1 indicates a perfect positive correlation (both variables move in the same direction),
-1 indicates a perfect negative correlation (one variable increases while the other decreases),
0 indicates no correlation (no relationship between the variables).
The Pearson correlation coefficient (r) is the most commonly used measure of correlation
and assesses the linear relationship between two continuous variables. It assumes that the
variables are normally distributed and measures how much one variable changes as the other
changes. The formula for Pearson correlation is:
Where:
Pearson correlation is useful when you want to assess the strength and direction of a linear
relationship.
Where:
Spearman is commonly used when the data is ordinal or when the relationship is not linear.
Correlation analysis is used to determine the strength and direction of relationships between
variables. When interpreting correlation results, consider the following guidelines:
Positive correlation: As one variable increases, the other also increases (closer to +1).
Negative correlation: As one variable increases, the other decreases (closer to -1).
No correlation: The variables do not move together in any discernible way (closer to 0).
18
While correlation helps identify relationships, it does not imply causation. A strong
correlation between two variables does not necessarily mean that changes in one cause changes
in the other; there may be other factors or variables influencing the relationship.
Example:
A Pearson correlation of 0.85 between hours studied and exam scores indicates a strong
positive relationship, meaning that more study hours are associated with higher exam scores.
A Spearman correlation of -0.75 between rank in a race and finish time suggests a strong
negative relationship; the faster the finish time, the higher the rank.
True Positives represent instances where the model correctly predicted the positive class.
For example, in a disease classification task, TP would be cases where the model correctly
identified patients as having the disease.
True Negatives are instances where the model correctly predicted the negative class. In the
same disease classification example, TN would be cases where the model correctly identified
patients as not having the disease.
False Positives, also known as Type I errors, occur when the model incorrectly predicts the
positive class for an actual negative instance. This would be when a healthy patient is wrongly
classified as having the disease.
False Negatives, or Type II errors, happen when the model incorrectly predicts the negative
class for an actual positive instance. In this case, the model fails to detect the disease in a patient
who actually has it.
19
5.3.1 ACCURACY
Accuracy is a measure of how often the model's predictions are correct, calculated as the
ratio of correct predictions (TP + TN) to the total number of predictions. It is useful when the
classes are balanced.
5.3.2 PRECISION
Precision measures the proportion of true positive predictions out of all positive predictions.
It is crucial when the cost of false positives is high.
5.3.3 RECALL
Recall, or Sensitivity, measures the proportion of true positive predictions out of all actual
positive instances. It is important in scenarios where missing positive instances (false negatives) is
costly.
5.3.4 F1 SCORE
The F1 Score is the harmonic mean of precision and recall, providing a single metric that
balances the trade-off between them. It is especially useful when the dataset is imbalanced, and both
false positives and false negatives are critical.
Computer Vision is a field of artificial intelligence (AI) that enables computers to interpret,
analyze, and understand visual information from the world, such as images and videos. It aims
to replicate human vision and automate tasks that require visual understanding. By extracting
and processing visual data, computer vision systems can perform tasks like image classification,
object detection, face recognition, and even self-driving car navigation.
Computer vision has rapidly evolved due to advancements in machine learning, especially
deep learning, which allows models to learn from vast amounts of visual data. It plays a critical
role in various sectors, including healthcare, retail, automotive, and robotics.
20
Fig 2: Computer Vision
Image processing involves manipulating and analyzing images to improve their quality or
extract useful information. Some commonly used techniques in image processing include:
1. Image Smoothing: This technique reduces noise and variations in an image, making it
clearer. Methods such as Gaussian Blurring or Median Filtering are used to smoothen
images by reducing unnecessary details.
2. Edge Detection: Detecting the boundaries of objects in images is crucial for identifying
shapes. Algorithms like Canny Edge Detection and Sobel Filters are widely used to detect
sharp transitions in pixel intensity, highlighting the edges of objects.
3. Thresholding: Thresholding converts grayscale images into binary images (black and
white) by setting a pixel intensity threshold. Pixels above the threshold are set to white, and
those below are set to black. This technique is used in applications like document scanning
and segmentation.
4. Morphological Operations: These operations, such as Erosion and Dilation, are used to
remove small objects or enhance structures within an image. They are commonly applied in
preprocessing tasks, such as noise removal or shape enhancement.
5. Image Segmentation: Image segmentation divides an image into meaningful regions or
segments. Watershed Segmentation and K-means Clustering are popular techniques to
separate objects from the background or other regions.
Object Detection involves locating and identifying objects within an image or video. It not
only classifies objects but also predicts their positions using bounding boxes. Object
Recognition, on the other hand, goes a step further by identifying specific instances of objects,
such as recognizing a particular face in a crowd or detecting a specific brand of a product.
1. Convolutional Neural Networks (CNNs): CNNs are the backbone of modern object
detection models. They can automatically learn features from images and are particularly
effective in tasks like image classification and face detection.
2. YOLO (You Only Look Once): YOLO is a real-time object detection algorithm that
divides an image into grids and predicts bounding boxes and class probabilities for objects
21
in a single pass through the network. It is widely used for tasks that require real-time object
detection, such as video surveillance or autonomous driving.
3. R-CNN (Region-based CNN): R-CNN family algorithms (e.g., Fast R-CNN, Faster R-
CNN) are another set of powerful object detection models. They first generate potential
object regions (proposals) and then classify each region using a CNN.
4. Haar Cascades: Haar Cascade classifiers are an older but efficient method for object
detection, especially in detecting faces. They work by applying multiple stages of classifiers
to an image to detect objects in real-time.
Convolutional Neural Networks (CNNs) are a class of deep learning models specifically
designed for analyzing visual data, such as images and videos. Inspired by the human visual
system, CNNs are highly effective in identifying patterns, textures, and objects in images,
making them the backbone of modern computer vision tasks. Unlike traditional neural networks,
CNNs take advantage of the spatial structure of images, allowing them to process data with a
grid-like topology efficiently.
CNNs are widely used in applications such as image classification, object detection, face
recognition, and even natural language processing. By using convolutional layers, CNNs can
automatically learn hierarchical feature representations, from simple features like edges and
corners to more complex features like shapes and objects.
A typical CNN consists of several key layers, each contributing to the extraction and
processing of image features:
22
1. Convolutional Layers: The convolutional layer is the core building block of CNNs. It
applies filters (or kernels) to the input image to detect features like edges, textures, and
patterns. This layer generates feature maps, which highlight the presence of specific features
across the image. Each filter produces a different feature map, helping the network capture
various aspects of the image.
2. Pooling Layers: Pooling layers are used to down-sample the feature maps, reducing their
spatial dimensions and computational complexity while preserving important features.
Common pooling techniques include Max Pooling (which selects the maximum value from
a window of the feature map) and Average Pooling. Pooling helps make the model invariant
to small translations in the input image, ensuring that the model can detect features
regardless of their location.
3. Fully Connected Layers (FC Layers): After the convolutional and pooling layers, the
network typically includes one or more fully connected layers. These layers take the high-
level features extracted by the convolutional layers and map them to the output classes. In an
image classification task, the final fully connected layer typically outputs a probability
distribution over the possible classes.
4. Activation Functions: Activation functions such as ReLU (Rectified Linear Unit) introduce
non-linearity into the network, allowing it to learn complex patterns. Without these non-
linear functions, the network would behave like a simple linear model.
5. Softmax Layer: In classification tasks, the final layer of a CNN is usually a Softmax layer,
which converts the output into probabilities for each class.
Transfer learning is a technique where a model that has been pre-trained on a large dataset is
fine-tuned on a smaller, domain-specific dataset. In the context of CNNs, popular pre-trained
models such as VGG, ResNet, Inception, and MobileNet are trained on massive datasets like
ImageNet, which contains millions of labeled images across thousands of categories.
By leveraging transfer learning, the pre-trained model’s convolutional layers can be used to
extract relevant features from a new dataset, while the fully connected layers can be re-trained
to suit the specific task. This approach saves time and computational resources and often leads
23
to improved performance, particularly when the target dataset is small or similar to the pre-
trained dataset.
Transfer learning is especially effective in scenarios where labeled data is scarce, as the pre-
trained model already has a good understanding of general features like edges, textures, and
shapes. Fine-tuning these models can significantly reduce the need for extensive training and
improve the performance of image classification tasks.
Natural Language Processing (NLP) is a subfield of artificial intelligence (AI) that focuses
on the interaction between computers and humans through natural language. The primary goal
of NLP is to enable machines to understand, interpret, and generate human language in a
meaningful way. It encompasses various tasks, including language translation, sentiment
analysis, text summarization, and conversational agents like chatbots.
NLP combines computational linguistics, machine learning, and linguistics to analyze and
understand human language. With the increasing volume of text data generated daily—from
social media, emails, articles, and customer reviews—NLP has become essential for businesses
and researchers seeking to extract insights from unstructured text. Advances in deep learning
and the availability of large datasets have significantly improved NLP models, enabling them to
achieve impressive performance in tasks such as text classification and language generation.
Text preprocessing is a crucial step in NLP that involves transforming raw text into a clean
and structured format suitable for analysis. This step helps to improve the performance of NLP
models by reducing noise and standardizing the input data. Common text preprocessing
techniques include:
1. Tokenization: Tokenization is the process of breaking down text into smaller units, called
tokens. Tokens can be words, phrases, or sentences, depending on the granularity required
for analysis. For example, the sentence "Natural Language Processing is fascinating!" can be
tokenized into ["Natural", "Language", "Processing", "is", "fascinating", "!"].
2. Lowercasing: Converting all text to lowercase helps to ensure consistency by treating words
with different casing (e.g., "NLP" and "nlp") as the same token.
3. Removing Punctuation and Special Characters: Punctuation marks and special characters
often do not contribute to the meaning of the text and can be removed to simplify analysis.
For instance, "Hello, world!" would become "Hello world".
4. Stopword Removal: Stopwords are common words like "and," "the," and "is" that often do
not add significant meaning to the text. Removing stopwords can reduce the dimensionality
of the data and improve model performance.
5. Stemming and Lemmatization: Stemming involves reducing words to their base or root
form (e.g., "running" to "run"), while lemmatization considers the context and converts
words to their dictionary form (e.g., "better" to "good"). Both techniques help standardize
words and reduce variations.
Once text has been preprocessed, the next step is to represent it in a format that machine
learning models can understand. Several text representation techniques include:
24
1. Bag of Words (BoW): The Bag of Words model represents text as an unordered collection
of words, disregarding grammar and word order. Each document is converted into a vector
of word frequencies, where each dimension corresponds to a unique word in the vocabulary.
While simple, BoW does not capture word context or relationships.
2. Term Frequency-Inverse Document Frequency (TF-IDF): TF-IDF improves upon BoW
by weighing the frequency of words relative to their importance in a collection of
documents. It assigns higher weights to words that are frequent in a particular document but
rare across the entire corpus, helping to identify key terms.
3. Word Embeddings: Word embeddings, such as Word2Vec, GloVe, and FastText, represent
words as dense vectors in a continuous vector space. These embeddings capture semantic
relationships and contextual meanings, allowing similar words to have similar vector
representations. For example, the words "king" and "queen" would have embeddings that
reflect their relationship in context.
4. Transformers: Transformers, particularly models like BERT and GPT, have revolutionized
text representation by using self-attention mechanisms to capture contextual information and
relationships between words in a sentence. These models have achieved state-of-the-art
performance in various NLP tasks.
Sentiment analysis is an NLP task that involves determining the sentiment or emotional tone
of a piece of text. It is widely used in applications like social media monitoring, customer
feedback analysis, and brand reputation management. Sentiment analysis can be categorized
into:
1. Binary Sentiment Analysis: This involves classifying text as either positive or negative.
For example, a review stating, "I love this product!" would be classified as positive.
2. Multi-class Sentiment Analysis: This expands on binary sentiment analysis by including
neutral or multiple sentiment categories (e.g., positive, negative, neutral). This approach
provides a more nuanced understanding of public opinion.
3. Aspect-Based Sentiment Analysis: This advanced technique analyzes sentiments towards
specific aspects of a product or service. For instance, in the sentence "The battery life is
great, but the camera quality is poor," the sentiment is positive towards battery life and
negative towards camera quality.
25
6. CONCLUSION
Through this project, I gained practical experience in data collection, preprocessing, model
development, and evaluation, essential steps in the machine learning workflow. The house price
prediction task demonstrated how machine learning models can uncover valuable insights from data
and provide accurate predictions based on historical patterns. By applying supervised learning
techniques like linear regression, I was able to develop a simple yet effective model to predict
housing prices based on various features.
This not only deepened my understanding of fundamental machine learning concepts but also
enhanced my skills in handling real-world datasets, building predictive models, and evaluating their
performance.
26
7. ANNEXURE
The Housing Price Prediction Model aims to predict the price of houses based on various
features such as location, size, number of bedrooms, and other factors. By utilizing machine
learning algorithms, particularly linear regression, the model analyzes historical data to establish
a relationship between housing features and their respective prices. This project showcases how
machine learning can be applied in the real estate market to make informed decisions based on
data patterns.
7.2 PURPOSE
The primary purpose of this project is to develop a model that accurately predicts house
prices using regression techniques. By feeding historical housing data into the model, it will
learn the relationship between various features and the house prices, enabling it to predict the
price of new houses based on their features. This helps buyers, sellers, and real estate agents
make more data-driven decisions.
7.3 PROCEDURE
1. Data-Collection:
We collect housing data from reliable sources, including features like house size, number of
rooms, location, and price.
2. Data Preprocessing :
Handling Missing Values: Any missing values in the dataset are handled by either filling them
with mean/median or removing them.
Feature Scaling: Standardization or normalization of features is performed to ensure they are
on the same scale, which improves model accuracy.
Encoding Categorical Variables: Categorical variables (e.g., location) are converted into
numerical representations using techniques like one-hot encoding.
3. Splitting Data :
The dataset is split into two parts: training and testing sets. Typically, 80% of the data is
used for training, and 20% is used for testing.
4. Model Building :
The Linear Regression algorithm is applied to the training data. The model learns the
relationship between the features and the house prices during this phase.
27
5. Model Evaluation :
The trained model is evaluated using the testing dataset. Evaluation metrics such as Mean
Squared Error (MSE) and R-squared (R²) are used to measure how well the model performs.
6. Prediction :
The model is used to predict the prices of houses based on the input features
7.4 IMPLEMENTATION
1. INSTALL LIBRARIES
Ensure that you have the required libraries installed in your Python environment.
pip install pandas numpy scikit-learn jupyter.
jupyter notebook
This will open the Jupyter interface in your browser. You can create a new notebook by clicking
on "New" and selecting "Python 3."
Import the necessary libraries for data handling, model building, and evaluation.
import pandas as pd
import numpy as np
28
from sklearn.metrics import mean_squared_error, r2_score
Load your housing dataset (assumed to be in CSV format) and perform basic exploration.
# Load the housing dataset (replace 'housing.csv' with your dataset path)
data = pd.read_csv('housing.csv')
data.head()
Handle missing values and split the dataset into features and target variables.
data.fillna(data.mean(), inplace=True)
# Split the dataset into features (X) and target variable (y)
model = LinearRegression()
model.fit(X_train, y_train)
29
# Predict house prices using the test data
y_pred = model.predict(X_test)
r2 = r2_score(y_test, y_pred)
Use the trained model to make predictions for new house data.
predicted_price = model.predict(new_house)
Execution :
1. Save the Notebook: After writing all the cells, save the notebook (File -> Save As) and run
the cells (Cell -> Run All).
2. Running the Notebook: You can run each cell one by one by clicking the "Run" button, or
you can run all cells at once (Cell -> Run All).
3. Exporting the Notebook: You can export the notebook as a PDF or HTML by going to File
-> Download As and selecting your preferred format.
7.5 TESTCASES
7.6 RESULTS
Fig 2: Results
The dataset used for the housing price prediction model contains key features such as
median income (`MedInc`), house age (`HouseAge`), average rooms (`AveRooms`), bedrooms
(`AveBedrms`), population (`Population`), occupancy (`AveOccup`), geographic coordinates
(`Latitude`, `Longitude`), and the target variable, housing price (`PRICE`). The data is
complete with no missing values, ensuring consistency for model training. The dataset was split
into a training set of 16,512 records and a test set of 4,128 records.
The model's performance was evaluated using Mean Squared Error (MSE), which was
calculated as 0.555, and the R-squared score was 0.576, indicating the model explained 57.6%
of the variance in housing prices.
31