Regression analysis is a statistical technique used to quantify the relationship between variables and determine the magnitude and direction of their effect. It can be used to understand how independent variables like price discounts influence dependent variables like sales. The document discusses how regression analysis would allow a hospital employee to determine which factors like diet, workload, medication, and age most influence patients' diabetes diagnoses. It notes regression analysis provides both multiple factor analysis and a quantifiable measure of each factor's impact. The most common types of regression analysis are linear and logistic regression.

1. Machine
Learning - I
Regression Analysis

2. What is regression?
 A regression is used to understand and quantify the
cause-effect relationships.
For example:
What will happen to the sales of a new brand if there is a
discount or offer of 15% for a particular week?
-- Sales might go up or down.
So, the cause here is the discount in price
and the effect is increase or decrease in sales
Rupak Roy

3. What is regression?
Now we want to know what is the impact on sales and by
how much.
This is will be called quantification of the impact.
Rupak Roy

4. What is Regression analysis?
Regression analysis is a statistical technique or we can also
say it is a mathematical approach used to infer the
magnitude and direction of a possible cause effect
relationship between the variables.
 Magnitude – size of impact
 Direction – positive or negative
Rupak Roy

5. What is regression analysis?
Problem statement:
Elsa works for a hospital and she is looking to understand the
factors that may influence diabetes of the patients.
How will she determine the factors that is influencing
diabetes ?
 Food habits ?
 Work Load ?
 Medication ?
 Age ?

6. What is regression analysis?
We can analyze the sample data and come out with
inferences about the population based on the sample, the
relationship between the variables available & the disease.
Are the variables:
 Food habits ?
 Work Load ?
 Medication ?
 Age ? have any impact on the disease?
Rupak Roy

7. Regression analysis?
What are the possible alternative ways to find out the
relationships?
 Visualization
 Correlations
But why then regression analysis?
Because regression analysis not only helps to find out the
relationship but also provides
• Multiple factor impact. For example like if we want to know
the combination of two variables have any effect on the
dependent variable/output or not.
• Quantification of the impact will provide measureable
value of factors on how much and how much will be the
impact for a particular event.
Rupak Roy

8. Regression analysis?
2 Mostly commonly used types of regression analysis are
 Linear
 Logistic
Let’s learn each of them in detail.
Rupak Roy

9.  Thank you.
Rupak Roy