The Cost of Stress: Evidence from Cashiers
Last registered on May 13, 2019

Pre-Trial

Trial Information
General Information
Title
The Cost of Stress: Evidence from Cashiers
RCT ID
AEARCTR-0004148
Initial registration date
April 29, 2019
Last updated
May 13, 2019 11:30 PM EDT
Location(s)

This section is unavailable to the public. Use the button below to request access to this information.

Request Information
Primary Investigator
Affiliation
NUS Business School
Other Primary Investigator(s)
PI Affiliation
NUS Business School
Additional Trial Information
Status
In development
Start date
2019-04-30
End date
2019-06-30
Secondary IDs
Abstract
This research comprises three studies investigating the compensating wage differential for cashier’s stress in dealing with payments made in cash. Hypothesis 1 is that, if cashiers incur stress from dealing with payments made in cash, then they must be paid a higher wage. Hypothesis 2 is that physiological measure of stress is greater when cashiers are dealing with payments made in cash than when dealing with payments made with card.

The first study exploits variation across countries and over time in the proportion of retail purchases in cash. It uses multi-country panel data to study cashier’s wages as a function of the proportion in cash and wages of other similarly skilled occupations.

The second study is a discrete choice “vignette experiment” in which cashiers at a major supermarket group in Singapore are required to choose between receiving payment by card and payment in cash with different monthly wages. This experiment enables the researcher to identify the compensating wage differential at which cashiers switch from preferring card to preferring cash, and also heterogeneity in the differential across cashiers with different background.

The third study is a laboratory experiment that studies the physiological effect of dealing with cash payments versus card payments.

The first and second studies are already underway. The objective of this application is to register the third study. Subjects in this experiment will take part in a series of cashier tasks. The manipulation is whether a high proportion of payments is made in cash. Stress level will be measured by heart rate variability (HRV), which will be monitored using an electrocardiogram (ECG) heart rate device attached to the subjects’ chest throughout the experiment.
External Link(s)
Registration Citation
Citation
Png, I.P.L. and Huan Yuen Charmaine Tan. 2019. "The Cost of Stress: Evidence from Cashiers." AEA RCT Registry. May 13. https://www.socialscienceregistry.org/trials/4148/history/46356
Experimental Details
Interventions
Intervention(s)
Subjects in this experiment will take part in a series of cashier tasks. The manipulation is whether a high proportion of payments is made in cash. Stress level will be measured by heart rate variability (HRV), which will be monitored using an electrocardiogram (ECG) heart rate device attached to the subjects’ chest throughout the experiment.
Intervention Start Date
2019-04-30
Intervention End Date
2019-06-30
Primary Outcomes
Primary Outcomes (end points)
The dependent variable is stress level, measured by heart rate variability (HRV).
Primary Outcomes (explanation)
HRV is a robust and established physiological indicator of stress (Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology, 1996; Falk et al., 2018).
Secondary Outcomes
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
This is a computerized laboratory experiment where subjects will be randomly assigned to a treatment with high proportion of payments in cash, or a treatment with high proportion of payments in card. Subjects will put on the heart rate monitoring device from the start to the end of the experimental session. They will participate in the cashier task using a computer or tablet device. We will vary the proportion of payments made in cash. In one treatment, a high proportion transactions is cash payment, and in another treatment, a high proportion transactions is card payment.
Experimental Design Details
Not available
Randomization Method
Subjects will be randomly be assigned to the treatment with high proportion of payments in cash, or the treatment with high proportion of payments in card, on the computer or tablet device.
Randomization Unit
Individual
Was the treatment clustered?
No
Experiment Characteristics
Sample size: planned number of clusters
150 students
Sample size: planned number of observations
150 students
Sample size (or number of clusters) by treatment arms
75 students in cash treatment, 75 students in card treatment
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
We conducted a pilot study with 12 subjects in April 2019. The power analysis (document uploaded) shows a required sample size of 129. We plan to include more students to account for missing or discrepant data.
Supporting Documents and Materials

There are documents in this trial unavailable to the public. Use the button below to request access to this information.

Request Information
IRB
INSTITUTIONAL REVIEW BOARDS (IRBs)
IRB Name
National University of Singapore Institutional Review Board
IRB Approval Date
2019-02-19
IRB Approval Number
S-17-252