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An experimental investigation of the influence of time perspective on emotionally moderated intertemporal choices

©2009 Diplomarbeit 56 Seiten

Zusammenfassung

Inhaltsangabe:Zusammenfassung:
In der vorliegenden Arbeit wird experimentell nach einem Einfluss der Zukunftsperspektive auf das durch Emotionen moderierte, zeitverzögerte Entscheidungsverhalten gesucht. Die Zukunftsperspektive wurde gemessen mit dem Zimbardo Time Perspective Inventory und mit dem Life-Space Sample. Das Entscheidungsverhalten wurde mit dem Delay Discounting Task untersucht und mit Hilfe der positiven bzw. aversiven Bilder aus dem international-anerkannten Bildersatz IAPS moderiert.
Anhand von drei Hypothesen wurde erwartet, dass die positiven Bilder eine kleine Diskontierungsrate in intertemporalen Wahlen verursachen und die aversiven Bilder eine große Diskontierungsrate bei den intertemporalen Wahlen verursachen. Das nächste erwartete Ergebnis betrifft die Zukunftsperspektive, gemessen mit dem Zimbardo Time Perspective Inventory. Hohe Zukunftsorientierung auf der Zimbardo Skala erklärt eine niedrige Diskontierungsrate in intertemporalen Wahlen, eine niedrige Punktzahl auf der Zukunftsskala des Zimbardo Time Perspective Inventory erklärt im Gegensatz dazu eine hohe Diskontierungsrate bei den intertemporalen Wahlen. Als letztes wurde eine positive Korrelation zwischen der Zukunftsorientierung erwartet, gemessen mit zwei verschiedenen Methoden der Messung der Zukunftsperspektive: Zimbardo Time Perspective Inventory und dem Life-Space Sample.
Von den erwarteten Ergebnissen wurde nur eins tatsächlich beobachtet, nämlich der Einfluss der positiven Stimmung auf das Entscheidungsverhalten. Weder die korrelative Beziehung der Zukunftsperspektiven, gemessen mit verschiedenen Methoden, noch der erklärende Einfluss der Zukunftsperspektive auf die Diskontierungsrate wurde gefunden.
Diese Ergebnisse stellen die Vergleichbarkeit der zwei Methoden der Messung der Zeitperspektive in Frage und weisen auch auf die Kompliziertheit des Konstrukts Zukunftsperspektive hin.
Abstract:
In the present study, we tested the hypothesis that future orientation and emotional states induced by stimulus material systematically influence the decision making process in the delay discounting task and the width of the time horizon. In particular, our three hypotheses were that the influence of scoring high on the future orientation survey regarding time perspective on the choices made between two derived in different times monetary rewards is moderated by manipulations of the two emotional dimensions of affective valence and arousal. Also expected was also the […]

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Inhaltsverzeichnis


Table of Content

Deutsche Zusammenfassung

Abstract

1.Theorie
1.1 Time Perspective
1.1.1 Future Time Perspective
1.1.2 Procedures for measuring Time Perspective
1.2 Delay Discounting
1.2.1 Procedures for measuring Delay Discounting
1.3 The influence of emotions on Time Perspective and Delay Discounting
1.4 Hypotheses

2. Method
2.1 Sample description
2.2 Instruments
2.2.1 Zimbardo Time Perspective Inventory
2.2.2 Delay Discounting task
2.2.3 International Affective Picture System
2.2.4 Life-Space Sample
2.3 Variables
2.4 Procedure
2.5 Design

3. Results

4. Discussion
4.1 Validity of the ZTPI
4.2 Validity of the Life-Space Sample
4.3 Delay Discounting ,Life-Space Sample and ZTPI
4.5 Future Time Perspective and Age

5. Implementations and future research

6.References

7. Appendix

A Tables

B Tests
B1 German version of ZTPI
B2 International Affective Picture System
B3 Delay Discounting task
B4 Life-Space Sample .

DEUTSCHE ZUSAMMENFASSUNG

In der vorliegenden Arbeit wird experimentell nach einem Einfluss der Zukunftsperspektive auf das durch Emotionen moderierte, zeitverzögerte Entscheidungsverhalten gesucht. Die Zukunftsperspektive wurde gemessen mit dem Zimbardo Time Perspective Inventory (Zimbardo & Boyd, 1999) und mit dem Life-Space Sample (Wallace, 1956). Das Entscheidungsverhalten wurde mit dem Delay Discounting Task (Kirby,1999)untersucht und mit Hilfe der positiven bzw. aversiven Bilder aus dem international-anerkannten Bildersatz IAPS ( Lang, Bradley, & Cuthbert, 2005) moderiert.

Anhand von drei Hypothesen wurde erwartet, dass die positiven Bilder eine kleine Diskontierungsrate in intertemporalen Wahlen verursachen und die aversiven Bilder eine große Diskontierungsrate bei den intertemporalen Wahlen verursachen. Das nächste erwartete Ergebnis betrifft die Zukunftsperspektive, gemessen mit dem Zimbardo Time Perspective Inventory (Zimbardo und Boyd,1999). Hohe Zukunftsorientierung auf der Zimbardo Skala erklärt eine niedrige Diskontierungsrate in intertemporalen Wahlen, eine niedrige Punktzahl auf der Zukunftsskala des Zimbardo Time Perspective Inventory erklärt im Gegensatz dazu eine hohe Diskontierungsrate bei den intertemporalen Wahlen. Als letztes wurde eine positive Korrelation zwischen der Zukunftsorientierung erwartet, gemessen mit zwei verschiedenen Methoden der Messung der Zukunftsperspektive : Zimbardo Time Perspective Inventory (Zimbardo und Boyd,1999) und dem Life-Space Sample (Wallace,1956).

Von den erwarteten Ergebnissen wurde nur eins tatsächlich beobachtet, nämlich der Einfluss der positiven Stimmung auf das Entscheidungsverhalten. Weder die korrelative Beziehung der Zukunftsperspektiven, gemessen mit verschiedenen Methoden, noch der erklärende Einfluss der Zukunftsperspektive auf die Diskontierungsrate wurde gefunden.

Diese Ergebnisse stellen die Vergleichbarkeit der zwei Methoden der Messung der Zeitperspektive (ZTPI und Life-Space Sample) in Frage und weisen auch auf die Kompliziertheit des Konstrukts Zukunftsperspektive hin.

ABSTRACT

In the present study, we tested the hypothesis that future orientation and emotional states induced by stimulus material systematically influence the decision making process in the delay discounting task and the width of the time horizon. In particular, our three hypotheses were that the influence of scoring high on the future orientation survey regarding time perspective on the choices made between two derived in different times monetary rewards is moderated by manipulations of the two emotional dimensions of affective valence and arousal. Also expected was also the influence of Future Orientation on the width of the Time Horizon. Two methods were used to measure the Future Orientation and the Time Horizon. Future Time Perspective was measured with the Zimbardo Time Perspective Inventory (Zimbardo & Boyd,1999) and the Life-Space Sample (Wallace,1956). Intertemporal choice behavior was assessed with a Delay Discounting task (Kirby,1999). In order to effectively manipulate two affective dimensions we used stimulus material previously standardized for affective valence and arousal (International Affective Picture Set, Lang, Bradley, & Cuthbert, 2005). Results derived on a sample of 60 participants in age 19-61 years confirmed the effect of mood on intertemporal choice (p < .05). The rest of expected outcomes was not statistically significant.

1.Theory

This chapter introduces the theoretical background to the experiment on the influence of time perspective on emotionally moderated intertemporal choices.

On the basis of previous theories and conceptualizations of Future Time Perspective (see sections 1.1.1, 1.1.2 and 1.2), expected was its influence on human choice behaviour when options are distant in time (intertemporal choices). I suspected that people who have a short Future Time Perspective (meaning that they don’t look far in the future) will underestimate the value of the delayed options. As an extension to that, people with extended abilities to look in the future will be more considerate about distant options. Intertemporal choice with options derived in different times can be also influenced by a person’s mood. It has been shown that emotional states make people behave in different manners than they are normally used to (1.3). I expect the mood manipulation to moderate the influence of future orientation on intertemporal choice.

There are many methods to capture Time Perspective (1.1.3), discounting delayed choice options (1.2.1) and mood manipulation procedures (1.3.1). Participants of the following experiment were given a questionnaire (ZTPI) to measure their Time Perspective, then after having seen a set of either ten positive or ten aversive pictures they were handed a form with 27 choices between two distant in time options: a smaller immediate reward or a bigger but distant one. In the end each participant was asked to list ten events that were going to happen in the future and predict his or her future age at the time each of those ten events happens. Since those three methods are considered to measure the Future Time Perspective I expected correlations between them and that choices of participants in the positive picture set group differed from the choices of participants in the aversive picture set group.

1.1. Time Perspective

“Time is a key to understanding people’s attitudes, thinking processes and behaviour. It’s only a passage of events that have happened, are happening or are about to happen” (Mbiti, 1974 cit. by Salzwedel, 1988). It is common to say that personal time is divided into three dimensions: past, present and future. To experience time it is necessary to understand these time dimensions, the relationship between them and their transition. Our attitude towards time varies and may affect our behaviour, the way we think and perceive the world , the decisions we make and many other aspects of our lives.

Time Perspective is an ambiguous concept that originates in a momentary cognitive representation of the transitive time dimension. The first definition of Time Perspective was done by William James: “Time Perspective is the knowledge of some other part of the stream, past or future, near or remote, that is always mixed in with our knowledge of the present thing” (James,W.,1890 cit by Zimbardo,2008). Later one could read another well-known social psychologist, Kurt Lewin name Time Perspective as “the totality of the individual’s views of his psychological future and his psychological past existing at a given time” suppressing its influence on ones current behaviour ( Lewin,1931,cit by Zimbardo & Boyd, 2008). Recent definition of Time Perspective points out even more its personalization: “Time perspective is the often unconscious personal attitude that each of us holds toward time and the process whereby the continual flow of existence is bundled into time categories that help to give order, coherence, and meaning to our lives” (Zimbardo & Boyd, 2008).

Time Perspective has many facets and dimensions. Thereby some scientists focus on emotional or social valence of the past, present or the future, and others on time dimensions and continuities between them. That being said, “Time Perspective is considered to have cognitive, emotional and social components” (Boniwell & Zimbardo, 2004).

Everyone has a Time Perspective that is largely unconscious and subjective and is associated with an habitual openness towards the future, present or the past, regulating one’s behaviour. Gorman and Wessman (1977) suggest that it is possible to regard temporal orientation, attitudes and experieces as persisting personality traits. Although Time Perspective may be affected by situational forces, such as inflation or facing survival stresses, it can also become a relatively stable dispositional chracteristic when a particular temporal bias comes to predominate one’s outlook and response hierarchy (Zimbardo & Boyd, 1999).

Time Perspective also has an influence on a person’s decision making process. For example, a past-oriented person would, before making a decision, compare a given situation with his or her own experience rather than a present- or future-oriented person. The latter would be likely to base their current decisions on anticipations or expectations of future events. Time Perspective is the totality of objects located within a more or less extended temporal zone insofar as they are virtually present to the subject in relation to his behaviour.(see Nuttin,1985). These objects can be seen as goal objects. Goal objects stimulate one’s actions and are situated at different moments in time (past or the future). All personal goal objects have their time when they are supposed to be achieved. “The human capacity to span time to an unlimited degree enables those distant goal objects to have an influence on the present behaviour“ (Nuttin,1985 ). The decision making process contains re- or constructing the past or the future in order to help the person see the importance and the (un)desirable consequences of the choice.

People tend to develop and overuse a particular Time Perspective. Future-oriented people are more likely to eat healthy food and exercise regularly. They are more successful professionally and academically and have fewer problems with planning their own future. Contrary to the future- oriented, present-oriented people tend to more risky and unhealthy behaviour. They are more likely to report abusing alcohol, drugs, and tobacco (Keugh, Zimbardo, & Boyd, 1999) but also seek pleasure and enjoy moments, are laid back and don’T have problems relaxing. Past–oriented persons seem to be bound in their past experiences which influence their current decisions.

“Time Perspective is regarded as an expression of a person’s own system of meanings that allows one to develop a coherent framework for living” (Lenings,1998, cit. by Boniwell & Zimbardo, 2004).

1.1.1. Future Time Perspective

This study focuses on one time dimension, the Future Time Perspective. The question of the future has been broadly explored in psychology. Future orientation is compared with a general preoccupation with the future or future events, and the ability to plan for the future. “Persons with high future orientation are characterized as pursuing their goals and engaging in daily planning of their activities, and preferring a problem solving approach” (Strathman, Gleicher, Boninger, & Edwards, 1994 ). The term Future Orientation contains affective, attitudinal, cognitive and motivational constructs, including the ability to imagine one’s future life circumstances (Greene,1986; Nurmi,1989a in Steinberg et al., 2009). ”It is created by the more or less distant goal objects that are processed by an individual. An extensive time perspective contributes to the subject’s setting of distant goals and to his elaborating long-term projects. Subjects with a short time perspective are handicapped in looking into the distant future” (Nuttin, 1985). Socio- emotional selectivity theory maintains that time horizons influence goals. When time is perceived as open-ended, goals are most likely to be preparatory, for example, gathering information, experiencing novelty and expanding breadth of knowledge. When constraints on time are perceived, goals focus more on objectives that can be realized in their very pursuit. Under these conditions, goals emphasize feeling states, particularly regulating emotional states to optimize well-being. (Mather & Carstensen, 2005).

Some researchers also mention the effect of the past on FTP in terms of using memories in constructing future behaviour. “Due to the memory, we are able to reconstruct the succession of previously experienced changes, and to anticipate such changes in the future”(Fraisse,1967, cit. by Nuttin, 1985).

Psychologists suggest that people tend towards shorter or longer future time perspectives and that these tendencies influence current behaviours and choices (Rothspan & Read, 1996; Strathman, Gleicher, Boninger, & Edwards, 1994 ).

1.1.2 Procedures for measuring Time Perspective

Few methods have been developed to measure the personal Time Perspective on the basis of combination of past, present, and future orientations. They contain self-reports and questionnaires that focus either on one (see Table 1.1.2.1) or all time dimensions (see Table 1.1.2.2).

Table 1.1.2.1

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Table 1.1.2.2

Attempts to capture more time dimensions.

illustration not visible in this excerpt

One of the psychologists involved in the research on the Future Time Perspective was Melvin Wallace, who described it as ‘the length of the future time span which is conceptualized’ (Wallace,M.,1956 cit by Kosakos,1971). His measure of the ‘future orientation’ is the temporal extension. Temporal extension describes how far into the future one is able to project one’s own life. The Life-Space sample by Wallace (1956) asks subjects to list a number of events (usually ten) that are going to happen in their future and afterwards write how old they will be when the event happens. The difference between the subjects‘ actual age and their predicted future age builds the future extension. The results of the test show the extent to which an individual thinks about and is concerned with various past and future consequences of his actions. Both the maximal and mean extensions are measures of the Future Time Perspective.

1.2. Delay Discounting Phenomenon

Delay Discounting tasks are another measure of capturing the Future Time Perspective. Making people make an intertemporal choice (in other words choose one of the two options derived in different times) also captures a person’s Time Perspective.

On average, people tend to choose options with immediate results rather than wait for the long-term consequences of their choices. “Delay discounting refers to the reduction in the present value of a future reward as the delay to that reward increases” (Kirby, Petry, & Bickel, 1999). This can be observed in various settings, like education, saving, dietary behavior etc. Making a choice is relatively easy when the options differ on a single dimension: individuals generally prefer a larger reward over a smaller one, as well as an earlier reward over a one provided later. Problems arise when choices differ on more than one dimension. The choice between a smaller reward available sooner and a larger reward available later is less obvious because it involves trading off costs and benefits occurring at different times (Frederick, Loewenstein and O’Donoghue 2002; Green and Myerson 2004; Soman, et al., 2005).

The motivation to resist immediate gratification depends on the subjective value of a delayed reward. The subjective value depends on both its magnitude and the amount of time before it becomes available. People tend to discount that value when it is distant in time according to the function

k= ((A-V)-1) / D

with k being the discount rate, A the value of delayed reward, V the value of immediate reward and D, length of delay (Mazur,1987). As k increases the person discounts the future more steeply.

People generally prefer small but soon payoffs to large but later ones, when the smaller payoff comes immediately. But when the same payoffs are distant in time, people tend to prefer the larger rewards, even though the time lag from the small to the larger would be the same as before (hyperbolic discounting). A number of subsequent experiments have confirmed that spontaneous choices by both human and nonhuman subjects follow a hyperbolic curve rather than the conventional exponential curve that would produce consistent choice over time (Kirby, 1997; Green, Fry, & Myerson, 1994).

There have been many attempts to understand and explain the phenomenon of discounting the value of a delayed reward. Some psychologists consider the concept of personal future. People shouldn’t care less about the future utility than the current utility, because both now and later are equal parts of one’s life. When one looks at life as a whole, preferring a small reward over a large one is irrational. “The belief that a person should weigh all utility the same, regardless of its temporal position, implicitly assumes that all parts of one’s future are equal parts of oneself; that there is a single, enduring , irreducible entity to whom all future utility can be ascribed” (see Broome (1991), Elster (1986), Jevons (1871), Lewis (1946), Pigou (1920), Ramsey (1928),Rawls (1971),and Sidgwick (1930) in Frederick, Loewenstein, & O'Donoghue, 2002).

Works on intertemporal choice behavior show that people neither think about their lives as a whole, nor about their present and future as equal parts. They often choose a small reward, because it is an immediate one. This way of thinking, the inability to clearly see the future consequences is also called myopia to the future. According to Salzwedel (1988) the anticipated delayed reward already exists in the future. Resisting the temptation of receiving the immediate or sooner gratification requires the ability to “see” the delayed one. The ability to “see” the delayed reward requires a certain sense of time to understand that the delayed option is yet to come, that the delayed option exists in the future

Research has shown that there are some factors other than time that may influence one’s choice. Delaying a reward reduces the value of that reward, and this delay discounting process may be influenced by visceral factors (Loewenstein,1996). “Visceral factors such as hunger, sexual desire, physical pain, cravings, and such have important implications for intertemporal choice because, by increasing the attractiveness of certain goods or activities, they can give rise to behaviours that look extremely impatient or even impulsive. Indeed, for every visceral influence, it is easy to think of one or more associated problems of self-control hunger and various “heat of the moment” behaviours, such as cravings, addictions and so on. They provide an alternate account of the preference reversals that are typically attributed to the hyperbolic time discounting, because the temporal proximity of a reward is one of the cues that can activate appetitive visceral states” (Loewenstein, Out of control: visceral influence on behaviors., 1996). An increase in desire, by physical or temporal proximity to rewards, may instigate impatience (Baumeister, 2002) and steeper delay discounting of rewards (Hoch & Loewenstein, 1991). Data collected in experiments on addicts (drug addicts, cigarette smokers, gamblers) confirmed that addicted people tend to choose immediate rewards while discounting the delayed ones ((Hodgins & Engel, 2002)(Kirby, Petry, & Bickel, 1999) (Bickel & Marsch, 2001(96)) (Bickel, Odum, & Madden, 1999) (Petry, 2001) )

1.2.1 Procedures for measuring Delay Discounting

The Delay Discounting phenomenon has been commonly studied within both psychology and economics. There are a number of experiments that focus on discounting the value of the delayed, future reward, however most of them contemplate a pool of monetary rewards. Methods to measure discount rates work with real or hypothetical rewards and can be divided into two categories: field studies, in which discount rates are inferred from economic decisions people make in their lives, and experimental studies, in which people are asked to evaluate stylized intertemporal prospects involving real or hypothetical outcomes (see Frederick, Loewenstein, & O'Donoghue, 2003). The most popular four experimental procedures vary between choice tasks, matching tasks, pricing tasks, and rating tasks. In a typical choice task subjects are asked to choose between a smaller, more immediate reward and a larger delayed reward. Matching tasks make subjects ‘fill in the blank’ to equate two intertemporal options. In rating tasks, subjects evaluate an outcome occurring at a particular time by rating its attractiveness or aversiveness. In pricing tasks, each respondent specifies a willingness to pay to obtain (or avoid) some outcome occurring at a particular time.

1.3 The influence of emotions on Time Perspective and Delay Discounting

“People are constantly engaged in emotionally driven behaviors. Because their behaviors are highly pervasive, psychological literature remarks the central meaning of emotional factors in most cognitive processes” (Damasio, 1994) such as, for example, decision making (see Loewenstein,1996). Theories on decision making often focus on intertemporal discounting as an aspect of decision making which is subject to emotional changes ( Loewenstein, 1996).

Whenever the reason of the emotional state is unrelated to the choice opportunities or to the objects of judgment, one can speak about incidental emotional responses (see Bodenhausen,1993). Incidental emotional responses, contrary to integral emotional responses, are often used as proxies for values. They include current emotions not caused by the target object, preexisting mood states and enduring emotional dispositions such as chronic anxiety. They have a variety of rational and irrational influences on judgments, decisions and behaviors, reasoning processes, the accuracy of one’s beliefs, one’s ability to exert self-control and the tendency to take risks.

“The presence of moods can cause individuals to act in manners which are contrary to their own long-term self-interest, often with full awareness that they are doing so” (Loewenstein, 1996; Loewenstein & O`Donoghue, 2004). Research has found that even stock market returns are sensitive to incidental emotions caused by sunshine”(Hirschleifer & Shumway, 2003, cit. by Loewenstein, G. & Rick, S.).

Positive emotions like happiness, joy or amusement also affect human behavior. People who feel happy may be influenced to reward themselves generously and to feel as if they have more freedom to act. “Emotions of happiness may influence the likelihood of self-gifts and explain immediate gratification (Mick and Faure, 1998 in Van den Bergh, Dewitte, & Warlop, 2008).

The evidence from recent studies on the influence of emotional distress on impulse control, measured by eating unhealthy food, procrastinating and delay discounting, shows that people are more likely to give in to their impulses when they are emotionally distressed and also convinced that this may change their mood. The research has shown an emotionally mediated connection between negative moods and impulse control. It indicates that negative states shift the priority among distressed individuals who seem to place the immediate goal of feeling better ahead of other goals (see Tice, Bratslavsky& Baumeister, 2001 in Gailliot & Tice, 2007). Negative affective states have been also found to reduce the ability to resist temptation and delay gratification among children (Fry,1995;Schwarz&Pollack 1977; Seeman & Schwarz 1974 cit. by Pham, 2007).

The theory and data indicate that threat-related negative emotional states bias people towards short-term thinking, favoring immediate consequences (Gray, 1999). He showed that subjects who were confronted with aversive slides from the International Affective Picture System repeatedly favored the option that had beneficial immediate effects, despite larger subsequent costs to the goal of doing well on the task. His experiment proved that the aversive pictures produce a bias to favor short-term outcomes.

1.4 Hypotheses

The following experiment was conducted to test the hypotheses derived from the prior theoretical considerations. This finding could help to improve to operationalization of Future Time Perspective, that seems to be a complicated construct. All three methods used in the experiment are considered to be measures of FTP, therefore I expect correlations between them. Also the role of the mood could show how sensitive the intertemporal choice is, and hence, could be manipulated.

My hypotheses are:

- Subjects in the negative mood discount rewards more and show a shorter time horizon than the subjects in the positive mood.

H0 : Subjects in the negative mood discount rewards same as or less than the ones in the positive mood; subjects in the negative mood show same as or extended time horizon as the ones in positive mood.

H1 : Subjects in the negative mood discount rewards more than the ones in the positive mood; subjects in the negative mood show shorter time horizon as the ones in positive mood.

- Subjects with a weak future perspective (measured with ZTPI) discount rewards more steeply and show a short time horizon (captured with the Life-Space sample). Subjects with a strong future perspective (measured with ZTPI) discount rewards less steeply and show a broad time horizon (captured with the Life-Space sample).

H0 : Subjects with a weak future perspective (measured with ZTPI) ) show a short time horizon (captured with the Life-Space sample) and discount rewards same as or less than the ones with a strong future perspective. Subjects with a strong future perspective (measured with ZTPI) discount rewards more steeply and show a broader time horizon (captured with the Life-Space Sample ).

H1 : Subjects with a weak future perspective (measured with ZTPI) discount rewards more steeply and show a short time horizon (captured with the Life-Space sample).

[...]

Details

Seiten
Erscheinungsform
Originalausgabe
Jahr
2009
ISBN (eBook)
9783836639415
DOI
10.3239/9783836639415
Dateigröße
750 KB
Sprache
Englisch
Institution / Hochschule
Technische Universität Berlin – Psychologie
Erscheinungsdatum
2009 (Dezember)
Note
2,0
Schlagworte
zeitperspektive delay discounting emotionen stimmung life-space sample
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Titel: An experimental investigation of the influence of time perspective on emotionally moderated intertemporal choices
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