Categorical predictors: Study brief


Data Analysis for Psychology in R 2

Author
Affiliation

Elizabeth Pankratz


Department of Psychology
University of Edinburgh
2025–2026

Conduct and report on an analysis that addresses the research aims.
The data is contained in two datasets available at: https://uoepsy.github.io/data/DapR2_S1B2_PracticalPart1.csv and https://uoepsy.github.io/data/DapR2_S1B2_PracticalPart2.csv

Study background and aims

The data used for this write-up exercise are simulated. They draw on a meta-analysis that explores the association between student characteristics and grades. The simulated data are loosely based on the findings of this work, and they expand on the methods and results reported in the paper:

Credé, M., Roch, S. G., & Kieszczynka, U. M. (2010). Class attendance in college: A meta-analytic review of the relationship of class attendance with grades and student characteristics. Review of Educational Research, 80(2), 272-295. https://doi.org/10.3102/0034654310362998

NOTE: You are not expected to write an introduction, so you do not have to read this article.

Method and procedure

The current study was split into two parts.

In the first part, researchers were interested in what might predict attendance in university courses. They collected information from 397 students across all years of study (Year; i.e., UG (Y1–Y4), MSc, and PhD), and recorded their class attendance across the academic year (Attendance), their level of Conscientiousness (Conscientiousness categorized as Low, Moderate, or High), the frequency of which they accessed online course materials (OnlineAccess categorized as Rarely, Sometimes, or Often), and the timing of class (Time categorized as 9AM, 10AM, 11AM, 12PM 1PM, 2PM, 3PM, 4PM).

In the second part, researchers were interested in how attendance across the year is associated with final course grades. They collected data from 200 students, recording their class attendance across the academic year (Attendance) and their final course grade (Marks, ranging from 0–100).

Research aim and questions

Research Aim

Explore the associations among academic outcomes, student/course characteristics (e.g., class time, online access), and attendance.

Research Questions

  • RQ1: Does conscientiousness, frequency of access to online materials, and year of study in university predict course attendance?
  • RQ2: Is there a difference in attendance between those with early/late classes in comparison to those with midday classes?
  • RQ3: Is class attendance associated with final grades?

Data dictionary

Data dictionary: Dataset 1

The data in DapR2_S1B2_PracticalPart1 contain six attributes collected from a simulated sample of \(n=397\) hypothetical individuals. It includes:

Variable Description
pid Participant ID number
Attendance Total attendance (in days)
Conscientiousness Conscientiousness (Levels: Low, Moderate, High)
Time Time of ulass (Levels: 9AM, 10AM, 11AM, 12PM, 1PM, 2PM, 3PM, 4PM)
OnlineAccess Frequency of access to online course materials (Levels: Rarely, Sometimes, Often)
Year Year of study in university (Levels: Y1, Y2, Y3, Y4, MSc, PhD)

Data dictionary: Dataset 2

The data in DapR2_S1B2_PracticalPart2 contain two attributes collected from a simulated sample of \(n=200\) hypothetical individuals. It includes:

Variable Description
Marks Final grade (0 to 100)
Attendance Total attendance (in days)