Water Consumption of Students at Dickinson College

Authors: Derek Chibbaro, Maia Vachon, Quang Nguyen, Ziwei Guo
Course: MATH 325
Institution: Dickinson College

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Project Overview

This project investigates the water consumption patterns among first-year students and upperclassmen at Dickinson College. By analyzing water usage data from residential buildings over a period of 10 semesters (Fall 2013 - Spring 2019), we aimed to determine if there is significant evidence that first-year students consume more water per person than upperclassmen. This analysis contributes to ongoing efforts to promote sustainability on campus.

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Objectives

The main objectives of this study are:

• To obtain a general understanding of the difference in water consumption between first-year students and upperclassmen.
• To assess whether first-year students consume more water per person than upperclassmen.

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Introduction

Water usage is an important indicator for evaluating sustainability in institutions. At Dickinson College, various efforts have been made to reduce water consumption, such as the installation of water bottle filling stations and the initiatives led by the Alliance for Aquatic Resource Monitoring (ALLARM). Our research extends this focus by analyzing whether specific student groups (first-years vs. upperclassmen) differ in their water usage, helping guide future resource conservation strategies on campus.

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Data Collection

The data used in this study was obtained from the Center for Sustainability Education at Dickinson College and consists of monthly water usage, recorded in centum cubic feet (CCF) for each building on campus from June 2011 to June 2021.

• Semesters covered:
  • Spring: January through May
  • Fall: September through December
• Excluded Data: Spring and Fall 2020 semesters were excluded due to the reduced campus population during the COVID-19 pandemic, which would have skewed results.

Data was further processed to reflect water consumption per person by filtering the records based on whether the buildings housed first-year or upperclassmen students, and then averaging the values across semesters. The buildings included:

• First-Year Buildings: Adams, Armstrong, Atwater, Longsdorf, Drayer, Baird McClintock, Spradley-Young, Conway
• Upperclassmen Buildings: Goodyear, Malcolm, Morgan, McKenney, Kisner-Woodward, Buchanan

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Methods

The analysis used a two-sample t-test to compare the mean water consumption per person between first-year students (( \mu_1 )) and upperclassmen (( \mu_2 )) over the 10 semesters, using unequal variances. The null hypothesis (( H_0 )) was that there is no difference in water consumption between the two groups, while the alternative hypothesis (( H_1 )) stated that first-year students consume more water.

• Null Hypothesis (( H_0 )): ( \mu_1 - \mu_2 = 0 )
• Alternative Hypothesis (( H_1 )): ( \mu_1 - \mu_2 > 0 )

Test Statistic Results:

• t-value: 2.13
• Degrees of Freedom: 16
• p-value: 0.024521

The p-value is less than 0.05, meaning we reject the null hypothesis at a 95% confidence level. This provides moderate evidence that first-year students consume more water per person than upperclassmen.

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Results and Conclusion

• Based on the statistical analysis, we concluded that first-year students consume more water per person than upperclassmen.
• Reasoning: Upperclassmen may consume less water due to their increased exposure to Dickinson's sustainability initiatives over time, making them more conscious of their water usage.
• This raises important questions about how to reduce water consumption, particularly among first-year students:
  • Could installing automatic sensor faucets in residential buildings help reduce water consumption?
  • Are there significant differences in water usage across different types of facilities (e.g., bathrooms)?

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Figures

• Figure 1: Screenshot of water usage per person, grouped by first-year and upperclassmen buildings for each semester.
• Figure 2: Line graph showing water usage per semester for both groups.
• Figure 3: Bar graph comparing mean water usage between the two groups.
• Figure 4: Normal Q-Q plot indicating a positive, linear relationship in the dataset.
• Figure 5: Shapiro-Wilk test results indicating that the water usage data for upperclassmen follows a normal distribution, while that for first-year students does not.

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Further Research Questions

• How can we further reduce water consumption among first-year students?
• Would installing automatic sensor faucets reduce water usage significantly?
• Should future studies consider comparing water consumption based on specific building facilities (e.g., bathroom, laundry room)?

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Acknowledgments

We would like to thank:

• Center for Sustainability Education at Dickinson College for providing the water usage data.
• Residence Life and Housing for the occupancy data.

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References

1. Water usage data was provided by the Center for Sustainability Education at Dickinson College on April 6, 2023.
2. Occupancy data was provided by Residence Life and Housing at Dickinson College on April 25, 2023.