1 Supplementary Materials
Index p. 2 Scripts of the manipulation of Study 1.
p. 5 Scripts of the manipulation of Study 2.
p. 11 Confirmatory Factor Analysis and Convergent-Discriminant Validity p. 16 Explorative analysis on the Self-Mental States Attribution (SMSA) scale p.18 Additional analysis on Human and Instrument Scores
2 Scripts of the manipulation of Study 1.
Study 1. Instrumental script.
Original version:
“Ok, sei il partecipante numero 23, accomodati qui. Bene che ci sei, mi mancano solo 10 partecipanti e avrò finito il lavoro.
Svolgerai un compito cognitivo al computer che testa le capacità di elaborazione e attenzione cognitiva. Ti appariranno dei quadrati e delle parole scritte con colori diversi. Dovrai indicare il colore col quale appaiono senza dare importanza quindi al significato delle parole. Nella prima pagina di questa attività comunque troverai delle spiegazioni dettagliate su come svolgere il compito.
Mi raccomando partecipante numero 23 la tua partecipazione e quella degli altri a questa attività è necessaria per concludere il mio studio.
In seguito all’attività poi dovrai rispondere a un questionario.
Ok, se non hai domande partecipante numero 23, proseguiamo.”
Il ricercatore apre la pagina iniziale dello Stroop sul computer.
“Ok, partecipante numero 23, leggi le istruzioni e inizia non appena sei pronto.”
Una volta terminato il compito:
“Ok partecipante numero 23, l’attività è finita, spero tu sia stato efficiente e abbia risposto correttamente al maggior numero di compiti possibili così che il mio studio abbia successo. Ora passiamo alla fase finale in cui devi compilare il questionario.”
English version:
"Ok, you're the participant number 23, sit here. Well you are here, I only need 10 participants and I will have finished the job.
You will perform a computer cognitive task that tests cognitive processing and attention skills. You will see squares and words written in different colors. You will have to indicate the color with which they appear without giving importance to the meaning of the words. On the first page of this activity you will find detailed explanations on how to carry out the task.
Remember participant number 23, your participation and that of others in this activity is necessary to finish my study.
After the activity you will then have to answer a questionnaire.
Ok participant number 23, if you have no question, we go on. "
The researcher opens the Stroop start page on the computer.
"Ok, participant number 23, read the instructions and start as soon as you are ready."
3 Once the task is over:
"Ok participant number 23, the activity is over, I hope you were efficient and that you correctly answered the greatest number of possible tasks so that my study is successful. Now let's go on to the final phase where you have to fill out the questionnaire. "
Study 1. Non instrumental script.
Original version:
“Ok, XXX (nome proprio del partecipante), accomodati qui. Bene che ci sei, sai per portare avanti lo studio la tua partecipazione è indispensabile e veramente preziosa.
Svolgerai un compito cognitivo al computer che testa le capacità di elaborazione e attenzione cognitiva. Ti appariranno dei quadrati e delle parole scritte con colori diversi. Dovrai indicare il colore col quale appaiono senza dare importanza quindi al significato delle parole. Nella prima pagina di questa attività comunque troverai delle spiegazioni dettagliate su come svolgere il compito.
Mi raccomando XXX, cerca di compiere il compito utilizzando al meglio le tue capacità in modo tale da poterle sviluppare per poter crescere e imparare attraverso questo compito.
In seguito all’attività ti chiederò di rispondere gentilmente a un questionario.
Ok XXX se hai delle domande fammele pure… (se ci sono il ricercatore risponde). No?
Allora proseguiamo.”
Il ricercatore apre la pagina iniziale dello Stroop sul computer.
“Ok XXX, leggi le istruzioni e inizia non appena sei pronto.”
Una volta terminato il compito:
“Ok XXX, l’attività è finita, spero tu l’abbia trovata stimolante e interessante. Ora passiamo alla fase finale in cui devi compilare il questionario.”
English version:
"Ok XXX (participants’ first name), sit here. Well you are here, you know, your participation is essential and truly precious to continue the study.
You will perform a computer cognitive task that tests cognitive processing and attention skills. You will see squares and words written in different colors. You will have to indicate the color with which they appear without giving importance to the meaning of the words. On the first page of this activity you will find detailed explanations on how to carry out the task.
Remember XXX, try to accomplish the task by making the best use of your skills so that you can develop them in order to grow and learn through this task.
4 After the activity, I will ask you to kindly answer a questionnaire.
Ok XXX if you have any questions let me know ... (if there are the researcher answers). No?
Then let's go on. "
The researcher opens the Stroop start page on the computer.
"Ok XXX, read the instructions and start as soon as you are ready."
Once the task is over:
"Ok XXX, the activity is over, I hope you found it stimulating and interesting. Now let's go on to the final phase where you have to fill out the questionnaire."
5 Scripts of the manipulation of Study 2.
Study 2. Common message.
Original version:
Gentile partecipante,
in questo studio ti sarà chiesto di partecipare a una brevissima simulazione lavorativa in cui lavorerai per pochi minuti per un giornale come correttore di bozze.
Ti sarà prima di tutto spiegato il tuo ruolo e poi procederai con lo svolgimento del compito lavorativo.
Il tempo per il tuo compito lavorativo è di 3 minuti.
Immagina quindi questi 3 minuti come se rappresentassero l’andamento di una tua giornata lavorativa. Cerca di fare del tuo meglio e non ti preoccupare se non finirai il tuo compito entro tale periodo di tempo.
Al termine di questo periodo di tempo infatti la pagina si chiuderà automaticamente e in seguito ti verrà chiesto di rispondere a delle domande su come ti sei sentito durante la simulazione.
Quando sei pronto clicca sul bottone rosso per entrare nel tuo ruolo lavorativo!
English version:
Dear participant,
in this study you will be asked to participate in a very short work simulation in which you will work for a few minutes for a newspaper as proofreader.
You will first be explained your role and then proceed with the performance of the work task.
The time for your work task is 3 minutes.
Imagine then these 3 minutes as if they represented the progress of a working day. Try to do your best and don't worry if you don't finish your task within that time.
At the end of this period of time the page will automatically close and then you will be asked to answer questions about how you felt during the simulation.
When you're ready, click on the red button to start your job role!
Study 2. Instrumental condition.
Original version:
Correttore numero 23,
Il giornale ‘Il Paese’ è uno storico quotidiano italiano, fondato a Milano il 5 marzo del 1886 e pubblicato da RCS MediaGroup. Il fondatore è Eraldo Torrente, il direttore è Ivano Bontana e la nostra sede si trova in via Angelo Pozzoli 8 a Milano. Il nostro slogan è: "La libertà delle idee”.
6 Sei stato assunto come correttore di bozze.
Ricoprendo tale ruolo, Il tuo compito sarà di leggere con attenzione gli articoli che devono essere pubblicati e correggerli: assicurati quindi che i testi siano corretti, non abbiano errori di ortografia o errori grammaticali.
La Direzione de “Il Paese”
Clicca sul bottone rosso per continuare
***************************************
Correttore numero 23, la tua collaborazione e quella degli altri correttori di bozze è per noi necessaria per rendere il giornale il più competitivo possibile e aumentarne il rendimento.
Nella prossima pagina ti presenteremo un articolo e nei prossimi tre minuti ti chiederemo di leggerlo attentamente riportando tutti gli errori che individuerai.
Correttore numero 23, è importante che tu svolga in maniera efficiente il tuo lavoro per raggiungere gli obiettivi del giornale.
Non appena sei pronto clicca sul pulsante rosso.
***************************************
Da quando si è aperta questa pagina è iniziata la tua giornata lavorativa. Fra 3 minuti la pagina si chiuderà automaticamente e verrai indirizzato alla pagina successiva.
Correttore numero 23,
leggi attentamente l’articolo riportato in questa pagina (132 anni di Coca Cola) e riporta tutti gli errori che individui (puoi copiare e incollare ogni parola o frase contenente l’errore) creando un elenco nel box che trovi qui sotto.
Ti chiediamo di riportare esattamente la parola errata che hai trovato. Per esempio: nella seconda riga appare un primo errore "ha". Il tuo compito è quello di riportare unicamente la parola nel box qui sotto in questo modo:
- ha
Pian piano che individuerai gli errori creerai quindi un elenco di parole errate.
Ricorda, è importante che tu svolga in maniera efficiente il tuo lavoro per aumentare il rendimento del giornale.
***************************************
Correttore numero 23,
la tua giornata lavorativa è terminata!
***************************************
7 English version:
Proof-reader number 23, Welcome to our team!
The newspaper ‘Il Paese’ is a historic Italian newspaper, founded in Milan on 5 March 1876 and published by RCS MediaGroup. The founder is Eraldo Torrente, the director is Ivano Bontana and our headquarters is located in Via Angelo Pozzoli 8 in Milan. Our slogan is: "The freedom of ideas".
You have been hired as a proofreader. In this role, your task will be to read carefully the articles that need to be published and to correct them: make sure that the texts are correct, having no spelling errors or grammatical errors.
The Directorate of "Il Paese"
Click on the red button to continue
***********************************
Proofreader number 23, your collaboration and that of the other proofreaders is necessary for us to make the newspaper as competitive as possible and increase its profit.
On the next page we will present an article and ask you to read it carefully, reporting all the errors you will identify.
Proofreader number 23, it is important that you do your job efficiently to achieve the goals of the newspaper.
When you feel ready, click on the red button.
***************************************
Your workday has started since this page opened. In 3 minutes, the page will close automatically, and you will be directed to the next page.
Proofreader number 23,
Read the article on this page carefully (132 years of Coca Cola) and report all the errors that you find (you can copy and paste every word or phrase containing the error) by creating a list in the box below.
8 We ask you to report exactly the misspelled word you found. For example: in the second line a first
"ha" error appears. Your job is to report only the word in the box below like this:
- has
As you identify the errors you will then create a list of misspelled words.
Remember it is important that you do your job efficiently to achieve the goals of the newspaper.
***************************************
Proofreader number 23, your working day is over!
********************************************************************************
Study 2. Non instrumental condition.
Original version:
Gentile collaboratore,
Benvenuto nel nostro team!
Il giornale ‘Il Paese’ è uno storico quotidiano italiano, fondato a Milano il 5 marzo del 1876 e pubblicato da RCS MediaGroup. Il fondatore è Eraldo Torrente, il direttore è Ivano Bontana e la nostra sede si trova in via Angelo Pozzoli 8 a Milano. Il nostro slogan è: "La libertà delle idee”.
Sei stato assunto come correttore di bozze. Ricoprendo tale ruolo, Il tuo compito sarà di leggere con attenzione gli articoli che devono essere pubblicati e correggerli: assicurati quindi che i testi siano corretti, non abbiano errori di ortografia o errori grammaticali.
Ti ringraziamo per la tua preziosa collaborazione, e ti auguriamo buon lavoro!
La Direzione de “Il Paese”
Clicca sul bottone rosso per continuare
***********************************
Gentilissimo, la tua collaborazione è veramente preziosa e indispensabile per il giornale.
Nella prossima pagina ti presenteremo un articolo e ti chiederemo di leggerlo attentamente riportando tutti gli errori che individuerai.
Ti chiediamo gentilmente di compiere il tuo lavoro utilizzando al meglio le tue capacità in modo tale da poterle sviluppare per poter crescere e migliorare nel tuo lavoro.
Quando ti senti pronto clicca sul bottone rosso.
***********************************
Da quando si è aperta questa pagina è iniziata la tua giornata lavorativa. Fra 3 minuti la pagina si chiuderà automaticamente e verrai indirizzato alla pagina successiva.
Gentile collaboratore,
9 leggi attentamente l’articolo riportato in questa pagina (132 anni di Coca Cola) e riporta tutti gli errori che individui (puoi copiare e incollare ogni parola o frase contenente l’errore) creando un elenco nel box che trovi qui sotto.
Ti chiediamo di riportare esattamente la parola errata che hai trovato. Per esempio: nella seconda riga appare un primo errore "ha". Il tuo compito è quello di riportare unicamente la parola nel box qui sotto in questo modo:
-ha
Pian piano che individuerai gli errori creerai quindi un elenco di parole errate.
Ricorda di fare del tuo meglio, utilizzando le tue capacità in modo tale da poterle sviluppare per poter crescere e migliorare nel tuo lavoro.
***********************************
Gentile collaboratore,
la tua giornata lavorativa è terminata!
***********************************
English version:
Dear collaborator, Welcome to our team!
The newspaper ‘Il Paese’ is a historic Italian newspaper, founded in Milan on 5 March 1876 and published by RCS MediaGroup. The founder is Eraldo Torrente, the director is Ivano Bontana and our headquarters is located in Via Angelo Pozzoli 8 in Milan. Our slogan is: "The freedom of ideas".
You have been hired as a proofreader. In this role, your task will be to read carefully the articles that need to be published and to correct them: make sure that the texts are correct, having no spelling errors or grammatical errors.
We thank you for your precious collaboration, and we wish you good work!
The Directorate of "Il Paese"
Click on the red button to continue
***********************************
Dear, your collaboration is truly precious and indispensable for the newspaper.
On the next page we will present an article and ask you to read it carefully, reporting all the errors you will identify.
We kindly ask you to do your job by making the best use of your skills so that you can develop them in order to grow and improve in your work.
10 When you feel ready, click on the red button.
***************************************
Your workday has started since this page opened. In 3 minutes, the page will close automatically, and you will be directed to the next page.
Dear collaborator,
Read the article on this page carefully (132 years of Coca Cola) and report all the errors that you find (you can copy and paste every word or phrase containing the error) by creating a list in the box below.
We ask you to report exactly the misspelled word you found. For example: in the second line a first
"ha" error appears. Your job is to report only the word in the box below like this:
- has
As you identify the errors you will then create a list of misspelled words.
Remember to do your best, using your skills so that you can develop them in order to grow and improve in your work.
***************************************
Dear collaborator, your working day is over!
********************************************************************************
11 Confirmatory Factory Analysis and Convergent-Discriminant Validity
The original set of scales of both the Studies included a further scale of self-objectification that is the Self-Mental State Attribution scale, SMSA (Baldissarri et al., 2014): the participants were asked to rate the extent to which they felt themselves able to experience 20 human mental states during the experimental session. Mental states referred to perceptions (e.g., hearing), thoughts (e.g., reasoning), wishes (e.g., wishing), intentions (e.g., planning) and emotions (e.g., fear, pleasure). The items were rated on a 7-point scale (1 = not at all; 7 = extremely). However, a Confirmatory Factor Analysis (CFA), Explorative Factor Analyses (EFA) and a following Discriminant and Convergent Validity Analysis showed that the employed scale had many cross-loading items and that the remaining items saturated into a bi-factorial solution that had problems of validity.
Furthermore, the original scale of the self-perception of instrument-like (vs human-like) considered 5 items for the human-related stimuli. However, the performed EFA and CFA showed that the item “someone” did not load properly on the related factor, so we did not consider it in the main analysis. It is important to note that the results considering also this item for the human score (Study 1: α =.78; Study 2: α =.83) are completely similar to the results presented in the present paper.
Below are reported in detail the analyses above mentioned.
Confirmatory Factor Analysis
First, we focused on Study 1 and we performed a CFA on the 33 items that composed the original questionnaire considering 4 latent factors (SMSA, Human Score, Instrument Score, Task engagement), but the model fit was not acceptable (e.g. RMSEA = 0.140, given the sensibility of χ2 to sample size and given the limitation of our sample size, we did not consider χ2 as a reliable indicator). Therefore, we performed an Explorative Factor Analysis, EFA, to explore the factorial structure of our items. The scree plot suggested 4/5 factors (Figure 1).
12 Figure 1. Scree plot of Study 1.
By analyzing the 4 factors solutions, we noted that this solution presented different items cross loading (>.3) on two or more factors, and that the extracted factors were not ascribable to a robust theoretical basis. In particular, SMSA items were the most problematic, suggesting an unexpected bi-factorial solution.
Therefore, we decided to analyze a 5 factors solution. In this case also, 8 items of the SMSA scale (i.e., thinking, deciding, reasoning, choosing, seeing, needing, willing and feeling pleasure) cross-loaded on more factors. Further, the item “someone” belonging to the human dimension of the main self-objectification measure unexpectedly loaded on the factor underlying the instrument- related stimuli. Therefore, in a series of further EFA analysis, we decided to delete these items. As reported in the Table below (Table 1), the final solution was a 5 factors model with 24 items.
13 Table 1. The five factors solution and the related factor loadings.
Factors
Items 1 2 3 4 5 Uniqueness
SMSA_3 0.845 0.2385
SMSA_2 0.772 0.4754
SMSA_8 0.762 0.1364
SMSA_4 0.736 0.5140
SMSA_6 0.711 0.2089
SMSA_7 0.684 0.4562
SMSA_12 0.646 0.3402
tool 0.874 0.1592
thing 0.864 0.2313
device 0.838 0.1664
instrument 0.780 0.3913
machine 0.707 0.4053
individual 1.019 0.0930
person 0.777 0.1066
human_being 0.725 0.1287
subject 0.681 0.3798
SMSA_15 0.784 0.3940
SMSA_13 0.757 0.4013
SMSA_19 0.744 0.3629
SMSA_20 0.626 0.4963
SMSA_14 0.489 0.6684
engagement_2 0.746 0.1806
engagement_1 0.623 0.1921
engagement_3 0.581 0.2768
Note. SMSA=Self-Mental States Attribution. 'Minimum residual' extraction method was used in combination with a 'oblimin' rotation.
The emerged factors were the instrument score, the human score, the task engagement and two factors underlying the SMSA.
The expected factor SMSA was split indeed into two factors that we labelled as SMSA_States and SMSA_Feelings. This bi-factorial solution can be due to the particular formulation of the SMSA items in the Italian language: all the items that loaded on SMSA_Feelings was related to perception of feelings (e.g., Durante la sessione sperimentale, mi sono sentito in grado di provare paura; engl transl: During the experimental session, I felt I was able to feel fear). All the items on SMSA_States
14 did not include feelings (e.g., Durante la sessione sperimentale, mi sono sentito in grado di vedere; engl transl: During the experimental session, I felt I was able to see).
Therefore, the final set of items on which we performed the 5 factors CFA was the following:
Instrument score: instrument, tool, device, thing, machine (all the original items) Human score: subject, individual, person, human being (4 of the 5 original items) Task engagement: engaged, committed, motivated (all the original items)
SMSA_States: expecting, planning, knowing, tasting, imagining, smelling, hearing SMSA_Feelings: attraction, embarrassment, desire, admiration, fear
The CFA performed on these items considering these 5 factors led to a quite acceptable model fit value, RMSEA=0.099. Therefore, we performed the same CFA on Study 2, obtaining acceptable model fit value, RMSEA=0.088.
Discriminant and Convergent Validity
Then, in order to demonstrate the discriminant validity of our scales, we considered the 5 factors and the related items emerged by the CFA. We adopted the Average Variance Extracted (AVE) approach
by using the Stat Tool Package retrieved on
http://statwiki.kolobkreations.com/index.php?title=Main_Page (Gaskin, 2016, "Validity Master", Stats Tools Package, http://statwiki.kolobkreations.com) that establishes the construct validity by considering the AVE as calculated on the basis of factors correlations and standardized regression weights resulted from the CFA.
Table 2 and Table 3 showed the results for Study 1 and Study 2, respectively.
Table 2. Study 1. Convergent and discriminant validity.
CR AVE MSV Engagement SMSA_
Feelings
SMSA_
States
Instrument Score
Human Score Engagement 0,920 0,793 0,500 0,890
SMSA_Feelings 0,816 0,477 0,076 0,085 0,691
SMSA_States 0,906 0,588 0,312 -0,559 0,275 0,767
Instrument Score 0,919 0,696 0,479 -0,692 0,072 0,542 0,835
Human Score 0,934 0,781 0,500 0,707 -0,027 -0,275 -0,673 0,884
Note. Validity concerns are in bold. SMSA=Self-Mental States Attribution; CR = Composite Reliability;
AVE = Average Variance Extracted, MSV = Maximum Shared Variance.Square roots of AVE are reported on the diagonal. Factor correlations are reported below the diagonal.
15 Table 3. Study 2. Convergent and Discriminant Validity.
CR AVE MSV Human
Score
SMSA_
Feelings
SMSA_
States
Instrument
Score Engagement Human Score 0,904 0,704 0,462 0,839
SMSA_Feelings 0,748 0,409 0,557 0,263 0,639
SMSA_States 0,832 0,417 0,557 0,418 0,746 0,645
Instrument Score 0,924 0,710 0,462 -0,680 -0,069 -0,169 0,843
Engagement 0,811 0,589 0,326 0,552 0,513 0,571 -0,357 0,768 Note. Validity concerns are in bold. SMSA=Self-Mental States Attribution; CR = Composite Reliability;
AVE = Average Variance Extracted, MSV = Maximum Shared Variance.Square roots of AVE are reported on the diagonal. Factor correlations are reported below the diagonal.
We can note that for both the Studies the only problematic scale is the SMSA, as we could expect on the basis of the CFA. In particular, Study 1 had a validity concern regarding the convergent validity of SMSA_Feelings, whose AVE was less than 0.50. We can note something similar for Study 2, in which we had validity concerns related to both the factors of SMSA. At one hand, there are lack of convergent validity for both SMSA_States and SMSA_Feelings (whose AVEs were less than 0.50), on the other hand there is a lack of discriminant validity between these two scores (the AVEs were less than the related MSVs and the square roots of the AVE were less than the absolute value of the correlation between these two factors).
Therefore, we can conclude that the SMSA scale, even when considering the two factors emerged by EFA and CFA, displayed a low convergent and discriminant validity in both studies.
For this main reason, as clarified in the manuscript (Footnote 1), we did not consider this measure in our main analyses.
Instead, the above analyses clearly supported a discriminant validity of the human score, the instrument score and task engagement, i.e., the crucial variables employed for correlational and serial mediation model analyses in the manuscript.
16 Explorative analysis on the Self-Mental States Attribution (SMSA) scale
Given the lack of validity of the two factors of the SMSA scale (SMSA_States, SMSA_Feelings) emerged by the previous analyses, we did not include the SMSA scale in the main text. However, we analyzed the possible effects of experimental conditions on them in an explorative way.
For both studies, each factor displayed a good internal reliability:
SMSA_States: Study 1 α = .91; Study 2 α =.81 SMSA_Feelings: Study 1 α =.81; Study 2 α =.75
Thus, we performed a series of t-tests for Study 1 and Study 2 in order to verify the effect of conditions on SMSA scores. In both the Studies, we found that conditions did not have an impact on SMSA (Table 4).
Table 4. Means (and standard deviations) for SMSA scores as a function of conditions and the related t-test analyses of Study 1 and Study 2.
Instrumental Condition
Non-Instrumental
Condition t-test
Study 1
SMSA_States 3.58(1.66) 3.23(1.68) t(83)=.94, p = .348 SMSA_Feelings 2.07(0.89) 2.53(1.52) t(83)= -1.74, p = .086
Study 2
SMSA_States 2.41(1.12) 2.55(1.19) t(145)= -.72, p = .473 SMSA_Feelings 2.01(1.02) 2.02(1.16) t(145)= -.05, p = .955 Note. SMSA=Self-Mental States Attribution.
Albeit the limitation of these analyses given the lack of validity of the SMSA scores, we speculated about the non-effect of the instrumental treatment on the self-attribution of mental states that define humanness, that usually has been employed in past studies to operationalize the objectification dimension of self-denial of humanity. Past studies (e.g. Auzoult & Personnaz, 2016; Baldissarri et al., 2014), albeit correlational, found a negative correlation between the workers’ perception of being instrumentally treated by superiors and their self-attribution of human mental states. In the present studies, instead, the manipulation of the instrumental treatment did not affect this peculiar self- attribution. The explanation could be twofold. First, it is plausible to imagine that the nature of our manipulation (i.e., instrumental vs. non instrumental treatment) led to a predominant outcome linked with the instrumental dimension of (self-) objectification, thus obscuring eventual effects on the other dimension concerning the (self-) denial of humanness. Another plausible explanation refers to the (brief) length of our experimental sessions and instrumental (vs. non instrumental) treatments. In fact,
17 if this time interval was enough to have an impact on the strictly related dimension of instrumentality, it is possible that it turned out as not enough to undermine the self-attribution of human mental states.
Indirectly supporting this line of reasoning, the correlational studies that supported the relationship between instrumental treatment and SMSA involved workers that perceived to be treated as instruments in their everyday work activity. Therefore, it is plausible that a prolonged and chronical instrumental treatment could have a significant impact also on the self-attribution of qualities that define humanness. Of course, such speculations should be better investigated through longitudinal studies that consider the temporal facet featuring the process of self-objectification and employ more valid measures assessing the self-denial of humanness.
18 Additional analysis on Human and Instrument scores
We ran the analyses conducted in the main text by considering the Human and the Instrument scores independently. The results confirmed the main findings of the analysis conducted with the single index of self-perception as instrument-like (vs. human-like).
In the instrumental condition, participants self-perceived as more instrument-like and as less human-like than participants in the non-instrumental condition (see Table 5).
Table 5. Means (and standard deviations) for Human and Instrument scores as a function of conditions and the related t-test analyses of Study 1 and Study 2.
Instrumental Condition
Non-Instrumental
Condition t-test
Study 1
Human Score 4.47(1.58) 5.13(1.35) t(83)= -2.07, p = .041 Instrument Score 3.28(1.57) 2.25(1.12) t(83)= 3.43, p = .001
Study 2
Human Score 4.27(1.54) 5.09(1.49) t(145)= -3.27, p = .001 Instrument Score 3.10(1.62) 2.37(1.45) t(145)= 2.81, p = .006
Furthermore, as shown in Table 6, both the two scores correlated with task engagement in both the studies. However, like the single index, they correlated with performance in Study 1 and not in Study 2.
Table 6. Correlations between the considered variables. Values of Study 1 are below the diagonal;
values of Study 2 are above the diagonal.
Variables 1 2 3 4
1. Human Score - -.60*** .45*** .08
2. Instrument Score -.63*** - -.31*** -.05
3. Task engagement .65*** -.66*** - .24**
4. Performance .51*** -53*** .77*** -
Note. *** p ≤ .001. ** p = .004.
Finally, for both the studies, we tested two serial mediation models considering the single scores separately and analyses confirmed that the indirect effects of condition on performance through the Human and Instrument scores and task engagement were significant (Table 7).
19 Table 7. Indirect effects of 4 serial mediation models considering the Human and the Instrument Scores independently.
Tested model Indirect effects
Study 1
1. Conditions - Human Score – Engagement - Performance a*b*c = -2.72, 95% CI [-5.72, -.14]
2. Conditions - Instrument Score – Engagement - Performance a*b*c = -4.45, 95% CI [-8.18, -1.60]
Study 2
3. Conditions - Human Score – Engagement - Performance a*b*c = -.09, 95% CI [-.18, -.02]
4. Conditions - Instrument Score – Engagement - Performance a*b*c = -.05, 95% CI [-.12, -.01]
