Exploring Research Question Formulation and Dataset Preview in a Bank Marketing Campaign Context

Apr 1, 2024, 2:21 PM

formulate a research question

Here's a preview of the dataset from the bank marketing campaign. It includes various attributes like age, job, marital status, education level, account balance, whether they have housing or personal loans, the communication channel used (contact), the day and month of the last contact, the duration of the last call, the number of contacts during this campaign, days since the client was last contacted from a previous campaign, the number of contacts before this campaign, the outcome of the previous marketing campaign, and finally, whether the client subscribed to a term deposit (deposit). This data can be used to analyze the effectiveness of different aspects of the marketing campaign.

formulate hypothesis on the key variables of interest

Based on the dataset, a potential hypothesis could be: The success of bank marketing campaigns (measured by the subscription to a term deposit) is significantly influenced by the communication channel used, the duration of the last call, and the client's account balance.
This hypothesis suggests that these key variables - communication channel, call duration, and account balance - might have a strong impact on the likelihood of a client subscribing to a term deposit. To test this hypothesis, we would analyze the relationship between these variables and the deposit subscription outcome.

Explore correlation between key variables and deposit subscription

We explored the correlation between key variables (communication channel, call duration, and account balance) and the subscription to a term deposit. The findings are summarized below:
  • Call Duration and Deposit Subscription: There's a positive correlation of 0.452, suggesting that longer calls are associated with a higher likelihood of subscribing to a term deposit.
  • Account Balance and Deposit Subscription: A positive correlation of 0.081 indicates a slight association between higher account balances and deposit subscriptions.
  • Communication Channel and Deposit Subscription: The negative correlation of -0.250 suggests that certain communication channels might be less effective in leading to deposit subscriptions.
These results support our hypothesis that call duration and the communication channel used significantly influence the success of bank marketing campaigns, as measured by deposit subscriptions. The account balance also shows a positive, albeit weaker, association.

Perform a logistic regression analysis to predict deposit subscriptions based on key variables

We performed a logistic regression analysis to predict the likelihood of a client subscribing to a term deposit based on key variables: call duration, account balance, and the communication channel used. Here are the key findings from the analysis:
  • Model Performance: The model shows a decent performance with a precision of 0.73, recall of 0.73, and an F1-score of 0.72 when predicting deposit subscriptions.
  • Confusion Matrix Analysis: The confusion matrix shows 946 true negatives (correctly predicted non-subscriptions), 220 false positives (non-subscriptions incorrectly predicted as subscriptions), 389 false negatives (subscriptions incorrectly predicted as non-subscriptions), and 678 true positives (correctly predicted subscriptions).
These results indicate that the logistic regression model, using call duration, account balance, and communication channel as predictors, can reasonably predict the outcome of deposit subscriptions in bank marketing campaigns.

Evaluate the impact of other variables on deposit subscriptions

To evaluate the impact of other variables on deposit subscriptions, we need to expand our analysis. This involves including additional variables from the dataset such as age, job, marital status, education level, whether the client has housing or personal loans, and details of previous marketing campaigns (e.g., number of contacts during this campaign, days since last contact from a previous campaign).
First, we'll encode these categorical variables to numeric ones for analysis and then re-train our logistic regression model with the expanded set of predictors. Let's proceed with encoding these additional variables and updating our model.
We expanded our logistic regression analysis to include additional variables such as age, job, marital status, education, housing, loan status, and details from previous marketing campaigns. Here's what we found:
  • Model Performance Improvement: The expanded model shows improved performance with a precision of 0.79, recall of 0.79, and an F1-score of 0.79. This indicates a better predictive capability compared to the initial model.
  • Confusion Matrix Analysis: The expanded model resulted in 937 true negatives, 229 false positives, 240 false negatives, and 827 true positives. This shows an improvement in correctly predicting both subscriptions and non-subscriptions to term deposits.
These findings suggest that including a broader set of variables can significantly enhance the model's ability to predict deposit subscriptions in bank marketing campaigns. The additional variables provide more context and insight into the factors influencing a client's decision to subscribe to a term deposit.

Continue the analysis

To continue the analysis further, we could explore several additional avenues:
  1. Feature Importance: Identify which variables have the most significant impact on predicting deposit subscriptions. This can help focus marketing efforts on the most influential factors.
  2. Model Optimization: Experiment with different machine learning models beyond logistic regression, such as decision trees, random forests, or gradient boosting machines, to see if they offer better predictive performance.
  3. Cross-Validation: Implement cross-validation techniques to ensure our model's performance is consistent across different subsets of the data and not just on a single test set.
  4. Hyperparameter Tuning: Fine-tune the model's hyperparameters to optimize its performance. This could involve adjusting the regularization strength in logistic regression or the depth of trees in decision tree-based models.
  5. Interaction Effects: Investigate the interaction effects between variables to see if combinations of features are more predictive of deposit subscriptions than individual features alone.
  6. Temporal Analysis: Since the dataset includes the month and day of contact, analyze how seasonal factors or specific times of the month impact the success of marketing campaigns.
Continuing with these steps will provide deeper insights and potentially improve the predictive accuracy of our model.

conclusion of the analysis based on the tested hypothesis

Our analysis began with the hypothesis that the success of bank marketing campaigns, as measured by the subscription to a term deposit, is significantly influenced by the communication channel used, the duration of the last call, and the client's account balance. Through correlation analysis and logistic regression, we found evidence supporting this hypothesis:
  • Correlation Analysis: Showed positive associations between call duration, account balance, and deposit subscription, and a negative association with certain communication channels.
  • Logistic Regression Analysis: The initial model, focusing on key variables, indicated that call duration and the communication channel have significant impacts on predicting deposit subscriptions. Expanding the model to include additional variables improved its predictive performance, confirming the importance of considering a broader set of factors.
In conclusion, our analysis supports the hypothesis that specific factors, including call duration, communication channel, and account balance, significantly influence the likelihood of a client subscribing to a term deposit following a bank marketing campaign. Further exploration into additional variables and model optimization could provide even deeper insights into the dynamics of customer behavior in response to bank marketing efforts.
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