Measurement Invariance of the Day Reconstruction Method: Results from the COURAGE in Europe Project

Given the growing interest in the study of subjective well-being as a measure of social progress, instruments that produce valid and reliable scores and that can be used within and across countries are needed. The aim of the present study was to analyze the measurement equivalence of the Day Reconstruction Method in its brief version, using nationally representative samples from Finland, Poland, and Spain obtained within the COURAGE in Europe project. The goodness-of-fit of a two-correlated-factors model and the reliability of the scores obtained were assessed. Cross-country invariance was tested employing a multiple group confirmatory factor analysis, through sequential constraint imposition. In each country, measurement invariance was tested across time frames (morning, afternoon and evening) and days of the week (weekday and weekend). The results found support for the hypothesis of a two-correlated-factors (positive and negative affect) structure; the reliability of the positive, the negative and the net affect scores showed appropriate values. A high equivalence across the three national samples was found: all items except one showed strong measurement invariance indicating that respondents from Finland, Poland, and Spain attribute the same meaning to the latent construct under study, and the levels of the underlying items are equal in all three countries. Similar results were found for the measurement equivalence across time frames and days of the week. Our findings support the assumption of comparability across the different samples considered; in general, higher positive affect and lower negative affect were found in Finland, in the evening and at the weekend.     

Do apes know that they could be wrong?

When confronted with uncertain or incomplete information in decision-making situations, monkeys and apes opt for either escaping the situation or seeking additional information. These responses have been interpreted as evidence of metacognitive abilities. However, this interpretation has been challenged. On the one hand, studies using the information-seeking paradigm have been criticized because subjects may simply engage in a search for information routine (e.g., search until spot the reward) without any metacognitive involvement. On the other hand, studies using the escape response paradigm have been criticized because subjects may not recognize their own state of uncertainty but have learned to use the escape response in the presence of certain stimuli configurations that create uncertainty. The current study attempted to address these two criticisms by presenting great apes (seven gorillas, eight chimpanzees, four bonobos, seven orangutans) with a seeking information task whose basic procedure consisted of presenting two hollow tubes, baiting one of them and letting subjects choose. Conditions varied depending on whether subjects had visual access to the baiting, the cost associated with seeking information, the time interval between baiting and choosing, the food quality and the additional information offered regarding the food’s location. Although subjects showed a high retrieval accuracy when they had witnessed the baiting, they were more likely to check inside the tube before choosing when high stakes were involved (Experiment 3) or after a longer period of time had elapsed between the baiting and the retrieval of the reward (Experiment 2). In contrast, providing subjects with indirect auditory information about the food’s location or increasing the cost of checking reduced checking before choosing (Experiment 1). Taken together, these findings suggest that subjects knew that they could be wrong when choosing.     

Object permanence in orangutans (Pongo pygmaeus), chimpanzees (Pan troglodytes), and children (Homo sapiens).

Juvenile and adult orangutans (n = 5; Pongo pygmaeus), chimpanzees (n = 7; Pan troglodytes), and 19- and 26-month-old children (n = 24; Homo sapiens) received visible and invisible displacements. Three containers were presented forming a straight line, and a small box was used to displace a reward under them. Subjects received 3 types of displacement: single (the box visited 1 container), double adjacent (the box visited 2 contiguous containers), and double nonadjacent (the box visited 2 noncontiguous containers). All species performed at comparable levels, solving all problems except the invisible nonadjacent displacements. Visible displacements were easier than invisible, and single were easier than double displacements. In a 2nd experiment, subjects saw the baiting of either 2 adjacent or 2 nonadjacent containers with no displacements. All species selected the empty container more often when the baited containers were nonadjacent than when they were adjacent. It is hypothesized that a response bias and inhibition problem were responsible for the poor performance in nonadjacent displacements.     

Great apes’ capacities to recognize relational similarity

Recognizing relational similarity relies on the ability to understand that defining object properties might not lie in the objects individually, but in the relations of the properties of various object to each other. This aptitude is highly relevant for many important human skills such as language, reasoning, categorization and understanding analogy and metaphor. In the current study, we investigated the ability to recognize relational similarities by testing five species of great apes, including human children in a spatial task. We found that all species performed better if related elements are connected by logico-causal as opposed to non-causal relations. Further, we find that only children above 4 years of age, bonobos and chimpanzees, unlike younger children, gorillas and orangutans display some mastery of reasoning by non-causal relational similarity. We conclude that recognizing relational similarity is not in its entirety unique to the human species. The lack of a capability for language does not prohibit recognition of simple relational similarities. The data are discussed in the light of the phylogenetic tree of relatedness of the great apes.     

Does the chimpanzee have a theory of mind? 30 years later

On the 30th anniversary of Premack and Woodruff's seminal paper asking whether chimpanzees have a theory of mind, we review recent evidence that suggests in many respects they do, whereas in other respects they might not. Specifically, there is solid evidence from several different experimental paradigms that chimpanzees understand the goals and intentions of others, as well as the perception and knowledge of others. Nevertheless, despite several seemingly valid attempts, there is currently no evidence that chimpanzees understand false beliefs. Our conclusion for the moment is, thus, that chimpanzees understand others in terms of a perception-goal psychology, as opposed to a full-fledged, human-like belief-desire psychology.     

How chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) perform in a modified emotional Stroop task

The emotional Stroop task is an experimental paradigm developed to study the relationship between emotion and cognition. Human participants required to identify the color of words typically respond more slowly to negative than to neutral words (emotional Stroop effect). Here we investigated whether chimpanzees (Pan troglodytes) would show a comparable effect. Using a touch screen, eight chimpanzees were trained to choose between two simultaneously presented stimuli based on color (two identical images with differently colored frames). In Experiment 1, the images within the color frames were shapes that were either of the same color as the surrounding frame or of the alternative color. Subjects made fewer errors and responded faster when shapes were of the same color as the frame surrounding them than when they were not, evidencing that embedded images affected target selection. Experiment 2, a modified version of the emotional Stroop task, presented subjects with four different categories of novel images: three categories of pictures of humans (veterinarian, caretaker, and stranger), and control stimuli showing a white square. Because visits by the veterinarian that include anaesthetization can be stressful for subjects, we expected impaired performance in trials presenting images of the veterinarian. For the first session, we found correct responses to be indeed slower in trials of this category. This effect was more pronounced for subjects whose last anaesthetization experience was more recent, indicating that emotional valence caused the slowdown. We propose our modified emotional Stroop task as a simple method to explore which emotional stimuli affect cognitive performance in nonhuman primates.     

Apes are intuitive statisticians

Inductive learning and reasoning, as we use it both in everyday life and in science, is characterized by flexible inferences based on statistical information: inferences from populations to samples and vice versa. Many forms of such statistical reasoning have been found to develop late in human ontogeny, depending on formal education and language, and to be fragile even in adults. New revolutionary research, however, suggests that even preverbal human infants make use of intuitive statistics. Here, we conducted the first investigation of such intuitive statistical reasoning with non-human primates. In a series of 7 experiments, Bonobos, Chimpanzees, Gorillas and Orangutans drew flexible statistical inferences from populations to samples. These inferences, furthermore, were truly based on statistical information regarding the relative frequency distributions in a population, and not on absolute frequencies. Intuitive statistics in its most basic form is thus an evolutionarily more ancient rather than a uniquely human capacity.     

A competitive nonverbal false belief task for children and apes

A nonverbal false belief task was administered to children (mean age 5 years) and two great ape species: chimpanzees (Pan troglodytes) and bonobos (Pan paniscus). Because apes typically perform poorly in cooperative contexts, our task was competitive. Two versions were run: in both, a human competitor witnessed an experimenter hide a reward in one of two containers. When the competitor then left the room (version A) or turned around (version B), the experimenter switched the locations of the containers. The competitor returned and reached with effort, but unsuccessfully, towards the incorrect container. Children displayed an understanding of the competitor's false belief by correctly choosing the other container to find the reward. Apes did not. However, in version A (but not version B), apes looked more often at the unchosen container in false belief trials than in true belief control trials, possibly indicating some implicit or uncertain understanding that needs to be investigated further.     

Engineering Ethics Beyond Engineers’ Ethics

Engineering ethics is usually focused on engineers’ ethics, engineers acting as individuals. Certainly, these professionals play a central role in the matter, but engineers are not a singularity inside engineering; they exist and operate as a part of a complex network of mutual relationships between many other people, organizations and groups. When engineering ethics and engineers’ ethics are taken as one and the same thing the paradigm of the ethical engineer which prevails is that of the heroic engineer, a certain model of the ideal engineer: someone both quite individualistic and strong enough to deal with all the moral challenges that could arise. We argue that this is not the best approach, at least today in our interrelated world. We have achieved a high degree of independence from nature by means of technology. In exchange for this autonomy we have become increasingly tied up with very complex systems to which we constantly delegate new tasks and powers. Concerns about safety keep growing everywhere due to the fact that now we have a sensitive awareness of the huge amount of power we are both consuming and deploying, thus, new forms of dialogue and consensus have to be incorporated at different levels, in different forums and at different times. Within these democratic channels of participation not just the needs and interests, but also the responsibilities and mutual commitments of all parties should be taken into account.