#70387 | AsPredicted

'Temporal Dynamics of Dehumanization: Regular TSA'
(AsPredicted #70387)

Created:       07/11/2021 12:25 PM (PT)

This is an anonymized version of the pre-registration.  It was created by the author(s) to use during peer-review.
A non-anonymized version (containing author names) should be made available by the authors when the work it supports is made public.

1) Have any data been collected for this study already?
It's complicated. We have already collected some data but explain in Question 8 why readers may consider this a valid pre-registration nevertheless.

2) What's the main question being asked or hypothesis being tested in this study?
Scholars have long argued that dehumanization facilitates mass violence by disengaging the moral restraints on harming fellow humans. However, two major challenges to this argument have emerged: (1) perpetrators wouldn't get any satisfaction from harming those they consider to lack human mental experiences (e.g., the capacity to experience suffering), which is at odds with the sadistic reality of genocidal violence, or (2) although dehumanization does play a role in mass violence, it's as a post-hoc rationalization that comes after perpetrators are already inured with killing. This project investigates the temporal dynamics of dehumanization of Jews in Nazi propaganda from 1927-45 in search of evidence consistent with one of these three possibilities.

The "classic hypothesis" that dehumanization facilitates violence would predict an increase trend in Nazi dehumanization of Jews during the lead-up to their attempted extermination (July 1941), while the "post-hoc hypothesis" would predict no decreasing trend until after the onset of the Holocaust, during which the increasing trend would then emerge. The "irrelevance hypothesis" would predict no trend either before or after the Holocaust.

3) Describe the key dependent variable(s) specifying how they will be measured.
Dehumanization will be measured with the Mind Overall variable generated by the Mind Perception Dictionary (Waytz & Schweitzer, 2020) for the Linguistic Inquiry Word Count software (LIWC; Pennebaker et al., 2015)

4) How many and which conditions will participants be assigned to?
NA - Archival data

5) Specify exactly which analyses you will conduct to examine the main question/hypothesis.
Following Jebb et al., 2015 (https://doi.org/10.3389/fpsyg.2015.00727), I will fit an interrupted time series model, with July 1941 as the "critical event", to the data. First, a regularly-spaced time series object will be created in R with all missing values included (i.e., no interpolation). The series will then be decomposed into its seasonal, trend, and irregular components. If necessary, the original series will be seasonally adjusted and/or transformed to stationarity and autocorrelation will be accounted for. Then the model will be fit to the data (again following Jebb et al., 2015).

6) Describe exactly how outliers will be defined and handled, and your precise rule(s) for excluding observations.
Months with fewer than 100 words of text will be excluded and coded as "NA"

7) How many observations will be collected or what will determine sample size?
No need to justify decision, but be precise about exactly how the number will be determined.

Sample size will be determined by the number of months in the archive that have 100+ words of text in Nazi propaganda directly related to Jews

8) Anything else you would like to pre-register?
(e.g., secondary analyses, variables collected for exploratory purposes, unusual analyses planned?)

"It's Complicated": The text corpus has already been assembled by a research assistant, but the first author has not yet analyzed it.

Additionally, the model described above will be compared with a model of the data with the missing values interpolated, as well as a model with an irregular time series dataset. The temporal dynamics of other aspects of dehumanization not limited to mind perception will also be explored with a custom-made LIWC dictionary constructed by myself, as will variables theoretically related to dehumanization (e.g., number of impersonal pronouns) with already-established LIWC dictionaries.