VALIDACIÓN LEAVE-ONE-OUT Y ANÁLISIS ROC EN CURVAS E

Twenty five people participated in this study, 10 women and 15 men. The entire expedition group consisted of 26 people however (including the experimenter). All crewmembers were adults who had applied to participate in the expedition (except for two girls aged 13 and 16 who accompanied their parents on the expedition) and had gone

through a selection processes based on the research they intended to conduct or the technical skills they could provide. Of the 26 people only 6 were not directly involved in a research program (two of whom were the children previously mentioned).

Duration of stay on the expedition varied from 5 days to 26 days with participants leaving and arriving each week. Only four people (including the experimenter) were present for the entire expedition while the majority of crewmembers (15) were present for two weeks or longer. In the first week there were 14 crew members, in the second week there were 17, in the third week there were 13 and there were 7 crewmembers during the final week of the expedition. On two occasions during the expedition the crew was divided into a home and away team. The first away mission was conducted during the second week of the expedition with 9 people spending 4 days away while 8 remained behind. The second away mission took place during the third week, with 5 people away for 2 days and 8 people remaining at the base.

Materials

A daily questionnaire was completed by the participants consisting of 26 questions covering a number of qualitative and quantitative domains.

The main qualitative measure employed in the questionnaire was a novel attempt to gauge which meaningful social identities people used in a given day. It asked participants to simply make a list of which groups they could identify themselves as being a member of. It was a self generated list without a fixed length, so that participants could write down as many or as few social groups as they liked. The list allowed for a qualitative picture of the ‘social map’ to be developed which described the social categories the crewmembers perceived. In this way it was used to address the issue of which social identities would emerge during the course of the expedition. In addition to this, the number of identities that a person recorded for a given day was taken as a measure of the variety of social identities employed by that person. This variable was referred to as “number of social identities”.

The next part of the questionnaire consisted of quantitative measures of a range of different variables. These included measures concerned with how much change people perceived in their social environment, how much pressure there was to conform with group norms, how strongly people identified with their group, how positively they felt towards their ingroup, how positively they felt towards a nominated outgroup, how different they perceived their own group to be from the nominated outgroup, how cohesive they perceived

their group to be, the degree to which the group embraced the diversity of its members, measures of personal and collective self esteem and measures of stress relating to social factors, goal/work related factors and general stress.

Social Environment Flux (SEF) was quantified by way of six Likert scale measures and one ratio measure. The Likert scale items were designed to measure the degree of variation in a participant’s social environment on a given day. As the concepts being measured were thought to be difficult for a person to count, scale measurements were used rather than ratio measures. Seven point Likert scales were employed which ranged from 1 to 7, with 1 indicating “few” or a “small number” and 7 indicating “many” or a “large number”. The aspects of SEF measured in this way included the range of; different tasks performed, different social roles undertaken, people who were physically present, goals pursued, different groups the participant observed interacting with one another, and information received from people not physically present. In addition to these, the participant was asked to provide an exact number of people that they had come into contact with on that day. The idea of quantifying the amount of change in a person’s social environment was entirely novel and as such; none of the measures used here had been trialled before.

During the remainder of the questionnaire, participants were asked to think about different aspects of group functioning. They were instructed to refer to the group they had nominated as “most important” in the first part of the questionnaire. In addition to this they were asked to nominate a group they did not feel part of. Measurements of group functioning were taken by asking participants the degree to which they agreed with a series of statements. They responded using Likert scales ranging from 1 to 7, with 1 representing “do not agree at all” and 7 representing “agree completely”.

The first aspect of group functioning they were asked to consider was how much pressure they felt to conform to the norms of their group. This was measured with two statements: “In our group, it is important for every one to do what is right by our group” and “When I do things I keep in mind what other members of my group would do”.

The next variables of group functioning to be measured were; how positively the participants felt towards their own group and then about a nominated outgroup. The statements used were: “Over the course of today I felt very positively towards my group” and “Today I felt very positively towards the other group”. In addition to this they were asked how different the two groups were with the reverse coded statement “My group and

the other group are quite similar to each other”. This was taken as a measure of group polarisation.

After this they were asked a question regarding the diversity norm of the group. This was done using the statement “To what degree do you think your group is generally open to new ideas about how to do things”.

Next the degree of ingroup identification felt towards their group was measured using the two statements “I feel strong ties with members of my group” and “I identify with other members of my group”. These measures have been used extensively in the past and were obtained from Doosje, Ellemers & Spears (1995).

Similarly the two measures of group cohesion were obtained from Stokes (1983) and have also been used reliably in past research. These measures used the statements “I would be delighted if the opportunity arose, at a later date, to undertake activities with the people who are in my group” and “Compared to other groups like mine, I believe that our group works very well together”.

Four items were used to assess the participants’ personal and collective self esteem. These were adapted from Rosenberg’s (1962) Self-Esteem Scale (the original items were only concerned with personal self esteem). The items presented to participants were: “On the whole I am satisfied with myself”, “I feel I do not have much to be proud of” (reverse scored), “Our group has much to be proud of” and “Other groups don’t think that our group is any good” (reverse scored).

The final three items in the questionnaire were used to measure stress levels in the participants. Firstly stress related to goals and work being done was measured with “Today I felt a large amount of stress, which was directly related to achieving my group’s goals”. Next social stress was measured with the reverse coded item “Working with other members of my group did not feel stressful at all”. The last item measured general stress levels with “Overall today was a very stressful day”.

The questionnaire then thanked participants for their time and effort.

Design and Analyses

As outlined earlier, this study was exploratory in nature and as such did not have a strict experimental design or specific hypotheses. The first issue, “social environment flux”, was investigated by seeing how the different aspects of SEF correlated with the number of social identities that a person generated on a given day. The second issue, “the

emergence of social identities” was investigated by qualitatively assessing the identities that people recorded. The third issue, “aspects of group functioning” was analysed using a correlational approach. This approach was flawed however as it made the assumption of independence of scores, where non-independence existed. It was utilised despite this for two reasons; firstly it is consistent with the methodology traditionally used in extreme environment research and secondly because it could be used as a rough guide to the nature of the relationships. Because of these shortcomings further multilevel linear modelling (MLM) was conducted to more accurately assess the relationships. In this way direct comparisons could also be made between the traditional correlational approach and the newer, MLM.

Procedure

The questionnaire was completed by participants at the end of each work day, usually just before or after dinner. Once the participants became accustomed to the questionnaires, it usually took them between 10 and 20 minutes to complete. Questionnaires were collected in locked boxes which were not opened until after the expedition, preserving individual confidentiality and addressing concerns regarding self- disclosure about group interactions while the expedition was ongoing. The questionnaires were also handled and analysed in such a way as to protect the confidentiality and anonymity of all participants post expedition, as far as possible.

Figure 4.2. Expedition Two Crewmembers complete psychological questionnaires.