Headphone and Loudspeaker Test (HALT)

The HALT is a test for detection whether online experiment takers use headphones or loudspeakers

Citation

We also advise mentioning the software versions you used, in particular the versions of the HALT and psychTestR packages. You can find these version numbers from R by running the following commands:

library(HALT)
library(psychTestR)
if (!require(devtools)) install.packages("devtools")
x <- devtools::session_info()
x$packages[x$packages$package %in% c("HALT", "psychTestR"), ]

Installation instructions (local use)

1. If you don't have R installed, install it from here: https://cloud.r-project.org/

2. Open R.

3. Install the ‘devtools’ package with the following command:

install.packages('devtools')

4. Install the HALT:

devtools::install_github('KilianSander/HALT', ref = "main") (The ref = "main" is needed for older github installation, as github changed the default branch name from "master" to "main" recently.)

Usage

Quick demo

You can demo the HALT at the R console, as follows:

# Load the HALT package
library(HALT)

Testing a participant

The HALT_standalone() function is designed for real data collection. In particular, the participant doesn't receive feedback during this version.

# Load the HALT package
library(HALT)

# Run the test as if for a participant, using default settings,
# saving data, and with a custom admin password
# You can specify a strategy how to use the test A, B  and C using a config object, which you can create using auto_config() and make_config()
HALT_standalone(config, admin_password = "put-your-password-here")

You will need to enter a participant ID for each participant. This will be stored along with their results.

Each time you test a new participant, rerun the HALT_standalone() function, and a new participation session will begin.

You can retrieve your data by starting up a participation session, entering the admin panel using your admin password, and downloading your data. For more details on the psychTestR interface, see http://psychtestr.com/.

The HALT currently supports English (en) and German (de [Du] and de_f [Sie]). You can select one of these languages by passing a language code as an argument to HALT_standalone(), e.g. HALT_standalone(languages = "de"), or alternatively by passing it as a URL parameter to the test browser, eg. http://127.0.0.1:4412/?language=DE (note that the p_id argument must be empty).

Installation instructions (Shiny Server)

1. Complete the installation instructions described under 'Local use'.
2. If not already installed, install Shiny Server Open Source: https://www.rstudio.com/products/shiny/download-server/
3. Navigate to the Shiny Server app directory.

cd /srv/shiny-server

4. Make a folder to contain your new Shiny app. The name of this folder will correspond to the URL.

sudo mkdir HALT

5. Make a text file in this folder called app.R specifying the R code to run the app.

• To open the text editor: sudo nano HALT/app.R
• Write the following in the text file:

library(HALT)
HALT_standalone(admin_password = "put-your-password-here")

• Save the file (CTRL-O).

6. Change the permissions of your app directory so that psychTestR can write its temporary files there.

sudo chown -R shiny HALT

where shiny is the username for the Shiny process user (this is the usual default).

7. Navigate to your new shiny app, with a URL that looks like this: `http://my-web-page.org:3838/HALT

Usage notes

• The HALT runs in your web browser.
• By default, image files are hosted online on our servers. The test therefore requires internet connectivity.