Understanding Simple Linear Regression
Introduction: In the world
of machine learning, predicting outcomes based on available data is a common
challenge. Consider the scenario where a friend seeks your assistance in
predicting the price of a new house in a particular locality. Without any
information about the features of the houses, this task seems insurmountable.
However, through the power of mathematics and regression, we can unravel the
mystery behind house prices. In this blog, we will delve into the concept of
Simple Linear Regression using an illustrative example to comprehend how this
technique can help us predict the price of the next house.
The Example: Imagine four
colonies, each with its corresponding house price: h1 - 40 lakhs, h2 - 70
lakhs, h3 - 75 lakhs, and h4 - 30 lakhs. Our goal is to predict the price of
the next house in h5. Initially, we lack any feature information for the
houses, making prediction challenging. But fret not; regression comes to our
rescue.
Plotting the Graph: To
understand the data better, we plot the house prices against their respective
colonies. The dotted lines on the graph represent average values. While these
averages might not be exact, they give us a rough idea of where the predicted
price lies. Now, we must calculate the error or loss for each house to assess
the accuracy of our predictions.
Incorporating House
Features: Now, imagine your friend provides you with another crucial piece of
information: the area of the respective houses - 60, 75, 90, and 40 square meters,
respectively. With this additional feature, we can create a new graph by
plotting the house areas against their prices.
The Concept of Independent
and Dependent Variables: In this context, area becomes the independent
variable, while the house price remains the dependent variable. We represent
the independent variable on the x-axis and the dependent variable on the
y-axis. Plotting the data points and joining them with a line, we create a
regression line. It could be either straight or curved, depending on the data
distribution.
Minimizing SSE and
Predicting h5 Price: The objective now is to minimize the SSE by adjusting the
regression line. By doing so, we achieve a line that best fits the data points,
enabling more accurate predictions. The SSE value reduces to 11, demonstrating
the improved performance of our regression model. With the feature information
and the area of h5 (70 square meters), we can effortlessly predict the house
price. Drawing a vertical line from the area value on the x-axis until it
intersects the regression line, we find that the predicted price lies between
40 and 70 lakhs. Therefore, the estimated price of h5 is 60 lakhs.
Conclusion: Simple Linear
Regression serves as a powerful tool to predict outcomes when equipped with the
appropriate features. In our example, we witnessed how incorporating the house
area as an independent variable drastically improved the accuracy of our
predictions. Whether it's house prices, stock market trends, or medical data,
regression techniques provide valuable insights into the relationships between
variables, making it an indispensable asset in the realm of machine learning.


Comments
Post a Comment