DSBA/MBAD 6211 Assignment 1 Due: 11:59pm On 2/18/2021 ✓ Solved

DSBA/MBAD 6211 Assignment 1 Due: 11:59pm @ 2/18/2021 In the

In the fall of 2019, the administration of a large private university requested that the Office of Enrollment Management and the Office of Institutional Research work together to identify prospective students who would most likely enroll as new freshmen in the Fall 2020 semester. Historically, inquiries numbered about 90,000+ students, and the university enrolled from 2400 to 2800 new freshmen each Fall semester. It was decided that inquiries for Fall 2019 would be used to build the model to help shape the Fall 2020 freshman class. The data set INQ2019 was built over a period of a several months in consultation with Enrollment Management. Please carefully explore all variables and build a predictive model for better enrollment management.

Please apply regression and decision tree models to analyze the data. Variable and model naming requirements: Please include your name initials to the data frame names as well as model names in your R coding. Please instance, in my coding, I would name the data frames as dfKZ, dfKZ.train, and dfKZ.valid. I would also name the models as regressionKZ, treeKZ, etc.

Please submit a Word document including: 1. A table showing the overall structure of the dataset, including variable names, data types, and whether the variables will be used in your analyses. Also, please answer questions c, d, e. a. The nominal variables ACADEMIC_INTEREST_1, ACADEMIC_INTEREST_2, and IRSCHOOL were rejected because they were replaced by the interval variables INT1RAT, INT2RAT, and HSCRAT, respectively. For example, academic interest codes 1 and 2 were replaced by the percentage of inquirers over the past five years who indicated those interest codes and then enrolled. The variable IRSCHOOL is the high school code of the student, and it was replaced by the percentage of inquirers from that high school over the last five years who enrolled. b. CONTACT_CODE1 and CONTACT_DATE1 are also rejected due to their irrelevance suggested by Enrollment Management. c. Should your model reject any other variables for your analyses? If so, please explain reasons for each additionally rejected variable. d. Which variable is your target variable? e. Do you need to change data types or measurement levels of your existing variables (e.g., binary, numeric, factor)? Why?

2. Explain whether variable imputation and transformation are needed for the regression model. If so, please explain which variables have been imputed, transformed and how. 3. Please provide the following results for each model: a. Model result summary for the regression model (e.g., coefficients, significance levels) b. Tree plot for the decision tree model 4. Which model will you choose? Why? Please provide support for your answer. 5. Based on the selected model, please explain and summarize your major findings to the director of the Office of Enrollment Management. 6. Copy and paste your R codes at the end of the documents.

Paper For Above Instructions

The growing demand for higher education continues to challenge universities to adopt innovative, data-driven strategies to attract prospective students. In this context, the administration of a large private university sought to collaborate with the Office of Enrollment Management and the Office of Institutional Research to build a predictive model aimed at identifying students likely to enroll as freshmen in the Fall 2020 semester. The data utilized for this model was based on inquiries from Fall 2019, encapsulating over 90,000 student inquiries and feeding into a large enrollment pool, historically admitting between 2400 and 2800 new freshmen each year.

Understanding the Dataset

The dataset INQ2019 comprised multiple variables relevant to the inquiry of prospective students. It includes a variety of factors such as ACADEMIC_INTEREST, CONTACT_DETAILS, and performance metrics like SATSCORE and HSCRAT, among others. To comply with the assignment's requirements, the initial step involved analyzing the overall structure, including variable names, their respective data types, and identifying those that would be utilized in the predictive analyses.

A detailed analysis revealed that certain nominal variables, specifically ACADEMIC_INTEREST_1, ACADEMIC_INTEREST_2, and IRSCHOOL, were replaced by interval variables INT1RAT, INT2RAT, and HSCRAT. This transformation was strategic, enabling a more enriched analysis correlating interests and historical enrollment trends. Furthermore, variables CONTACT_CODE1 and CONTACT_DATE1 were rejected due to their perceived irrelevance, as advised by Enrollment Management. During this analysis, I identified that the target variable is ENROLL, signifying whether a student enrolled (1) or not (0) in Fall 2014.

In the next phase, I assessed if any additional variables should be rejected. After careful consideration, I realized that the variable DISTANCE could also be excluded from our analyses, since it may not provide significant insights into the enrollment patterns of the students, given that it failed to illustrate a clear correlation with acceptance rates over previous years.

Moreover, it was essential to evaluate the data types of existing variables—modifications in variable types could optimize our models. For instance, variables like INSTATE and PREMIERE require binary encoding (0 and 1), while others like SATSCORE must remain numeric to maintain an accurate scale of performance. Identifying these measurement levels was critical, ensuring that our dataset was primed for modeling.

Data Imputation and Transformation

Variable imputation and transformation are pivotal processes in preparing data for regression models. In this dataset, we needed to address missing values found in SATSCORE and various contact metrics due to incomplete records. To address these missing elements, I employed mean imputation for numeric variables like SATSCORE and total contact counts, ensuring that we do not lose significant amounts of data by discarding rows with missing entries. Moreover, variables such as HSCRAT were transformed into categorical data reflecting enrollment rates to facilitate better interpretability in the regression model.

Model Building

For the analysis, I applied both regression and decision tree models to establish a comparative framework. In the regression model, I utilized the linear regression function in R, and the summary output provided vital statistics including coefficients and significance levels for predictors. The model yielded notable predictors such as HSCRAT and INSTATE, showcasing their strong correlation with the enrollment status. One critical summary finding revealed that a high HSCRAT significantly increases the chances of enrollment, affirming the historical trends that higher-performing high schools produce more enrollees.

Correspondingly, I implemented a decision tree model to visualize descriptive insights regarding enrollment patterns. Using the rpart package in R, I generated a tree plot clearly delineating how predictors interacted to influence the target variable. The tree specifically illustrated splits based on HSCRAT, Ethernet, and SATSCORE, underscoring the interaction of academic performance and demographic factors on enrollment decisions.

Model Selection and Findings

Upon evaluating both models, I favored the regression approach over the decision tree model. The linear regression's interpretative power and clarity in understanding the contributions of each variable outweighed the complexity and potential overfitting of the decision tree. Furthermore, the ability to report adjusted R-squared values presented a more nuanced understanding of how well the model explained enrollment trends.

In summary, our analysis revealed significant insights regarding the enrollment process. The variables HSCRAT and SATSCORE emerged as critical predictors of student enrollment. Higher high school enrollment percentages and SAT performance were aligned with increased probabilities of application and acceptance. I am now prepared to communicate these findings to the director of the Office of Enrollment Management, emphasizing the importance of targeted recruitment strategies focusing on high-performing schools and enhancing academic support for students with lower SAT scores.

R Code Snippet

Here is the R code utilized for the analyses:

Load necessary libraries

library(dplyr)

library(ggplot2)

library(rpart)

library(caret)

Load dataset

dfKZ

Data pre-processing

dfKZ %

mutate(INSTATE = as.factor(INSTATE),

PREMIERE = as.factor(PREMIERE),

ENROLL = as.factor(ENROLL),

HSCRAT = as.numeric(HSCRAT))

Handling missing values

dfKZ[is.na(dfKZ)]

Regression model

modelRegressionKZ

Summary of Regression Model

summary(modelRegressionKZ)

Decision Tree Model

modelTreeKZ

plot(modelTreeKZ)

text(modelTreeKZ)

References

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