18-09-2023

We discovered the interaction model today. When there are three or more variables present, interaction occurs when at least two of them combine in a way that affects the third variable in a way that is not just additive. In other words, the interaction between the two variables causes their combined effect to be greater than the total of their individual effects. When the impact of one variable depends on the value of another variable, this is known as an interaction effect.

Understanding and accounting for complex relationships in data requires the use of interaction models. They aid in identifying trends and improving the interpretation of the connections between the variables in their data.

15-09-2023

In class, we studied about the linear regression model today, along with some related subjects.

A common statistical technique for simulating the relationship between a dependent variable and one or more independent variables is linear regression. It presupposes that the predictors and the target variable have a linear relationship. Finding the best-fitting linear equation to reflect this relationship is the primary objective of linear regression.

Simple Linear Regression: One independent variable and one dependent variable (target) are used in simple linear regression. They are modeled as being connected in a straight line.

One dependent variable (the target) and two or more independent variables are used in multiple linear regression. The predictors are combined linearly to model the relationship.

13-09-2023

During today’s class, we gained insights into the importance of p-values and the null hypothesis within the context of simple linear regression:

P-value Explanation: The p-value gauges the probability of observing the data as it is, assuming that the null hypothesis holds true. A low p-value indicates strong evidence against the null hypothesis.

Hypothesis Testing: We compare the p-value to a significance level, often set at 0.05. If p ≤ the significance level, we typically reject the null hypothesis and favor an alternative hypothesis.

Significance of the Null Hypothesis: The null hypothesis serves as the initial assumption, representing the absence of an effect or relationship between variables. Additionally, we delved into the concept of Standard Errors (SE), which quantify the precision of coefficient estimates and facilitate the computation of confidence intervals.

Confidence Intervals: Confidence intervals offer a range of values that are likely to encompass the true parameter value with a specified level of confidence, often 95%. We can employ hypothesis tests on coefficients, such as β1, to ascertain if there exists a statistically significant relationship between variables. A small standard error coupled with a corresponding t-statistic may indicate that the coefficient significantly differs from zero, implying the presence of a relationship.

11-09-2023

In today’s lecture, we talked about the concept of linear regression and concepts related to working with the CDC Diabetes 2018 dataset.
It is a basic statistical technique for modeling the relationship between a dependent variable and one or more independent variables. It is a powerful tool for understanding and predicting how changes in the independent variable will affect the dependent variable.
To use the provided dataset i.e. H. CDC Diabetes 2018, we have discussed several statistical methods such as median, standard deviation, skewness, and kurtosis. The dataset consists of three variables: obesity, physical inactivity, and diabetes. There are 354 rows of data containing information about all three variables. We created diabetes rate and inactivity data descriptions for these 1370 shared data points. This step in statistical analysis allows you to understand and analyze your data.

linear regression

Exploratory Data Analysis
Load the diabetes dataset from the CDC.
Familiarize yourself with the data by viewing the initial entries, identifying any missing values, and summarizing key statistics.
Visualize the key features like obesity, inactivity, and diabetes to grasp their overall patterns, skewness, and peaks.
Examine how obesity, inactivity, and diabetes relate to one another through correlation.

Regression Modeling
Single Variable Regression:
Use inactivity as the predictor to forecast diabetes rates.
Multivariate Regression:
Utilize both inactivity and obesity as predictors to estimate diabetes rates.
Ensure that the assumptions of linear regression hold by inspecting the spread of the model residuals for heteroscedasticity.

Assessing Model Quality
Determine how well the regression models perform using relevant metrics, such as RMSE or the R^2 score.

To move forward, please share the CDC diabetes dataset. If it’s extensive, a subset will suffice. With the data on hand, we can initiate the exploratory analysis phase.