Philip G. Zimbardo

Putting Time in Perspective: A Valid, Reliable Individual-Differences Metric

Time perspective (TP), a fundamental dimension in the construction of psychological time, emerges from cognitive processes partitioning human experience into past, present, and future temporal frames. The authors’ research program proposes that TP is a pervasive and powerful yet largely unrecognized influence on much human behavior. Although TP variations are learned and modified by a variety of personal, social, and institutional influences, TP also functions as an individual-differences variable. Reported is a new measure assessing personal variations in TP profiles and specific TP biases. The five factors of the Zimbardo Time Perspective Inventory were established through exploratory and confirmatory factor analyses and demonstrate acceptable internal and test–retest reliability. Convergent, divergent, discriminant, and predictive validity are shown by correlational and experimental research supplemented by case studies.

Prosocial Foundations of Children's Academic Achievement

The present longitudinal research demonstrates robust contributions of early prosocial behavior to childrens developmental trajectories in academic and social domains. Both prosocial and aggressive behaviors in early childhood were tested as predictors of academic achievement and peer relations in adolescence 5 years later. Prosocialness included cooperating, helping, sharing, and consoling, and the measure of antisocial aspects included proneness to verbal and physical aggression. Prosocialness had a strong positive impact on later academic achievement and social preferences, but early aggression had no significant effect on either outcome. The conceptual model accounted for 35% of variance in later academic achievement, and 37% of variance in social preferences. Additional analysis revealed that early academic achievement did not contribute to later academic achievement after controlling for effects of early prosocialness. Possible mediating processes by which prosocialness may affect academic achievement and other socially desirable developmental outcomes are proposed.

Who's smoking, drinking, and using drugs? Time perspective as a predictor of substance use.

Two studies examined whether those identified as having a more present time perspective (PTP) are more likely to report using alcohol, drugs, and tobacco. In Study 1, across 2,627 participants from 15 samples, we found that PTP, as assessed by the Zimbardo Time Perspective Inventory, was related to more frequent self-reported alcohol, drug, and tobacco use (Substance Use scale: average r = .34, p <.001). Future time perspective (FTP) was negatively related to reported substance use (average r = -.16, p < .001), but the relation was weaker than that of PTP, suggesting that PTP and FTP are independent constructs. In Study 2, we found that PTP was a significant predictor of reported substance use even after controlling for many personality traits that have been related to increased substance use. These findings indicate that time perspective is an important individual difference construct that should be considered when examining health-related behaviors, such as substance use and abuse, and in planning inter...

Present time perspective as a predictor of risky driving

This research introduces a new individual difference variable, time perspective, as an important predictor of risky driving. Across three separate replications, with 2863 participants, present time perspective is significantly correlated with reported risky driving behaviors. Its effect is greater than, and independent of, the negative correlations between future time perspective and risky driving. Additionally, males are more present-oriented and report taking more risks than females, while females are more future-oriented. Regression analyses and discriminate validity assessments demonstrate that present time perspective remains an independent predictor of risky driving even when pitted against nine other measures previously reported as related to driving risk, such as, sensation seeking, impulsivity, and aggression. Although complicated by the number of factors potentially involved, it is imperative to attempt to predict such risk because of the enormous economic and psychological toll resulting from auto accidents and fatalities related to risky driving. Discussion centers on implications for education based on understanding the psychological dynamics of time perspective and links to general risk-taking and self-regulation. Language: en

A Global Look at Time: A 24-Country Study of the Equivalence of the Zimbardo Time Perspective Inventory

In this article, we assess the structural equivalence of the Zimbardo Time Perspective Inventory (ZTPI) across 26 samples from 24 countries (N = 12,200). The ZTPI is proven to be a valid and reliable index of individual differences in time perspective across five temporal categories: Past Negative, Past Positive, Present Fatalistic, Present Hedonistic, and Future. We obtained evidence for invariance of 36 items (out of 56) and also the five-factor structure of ZTPI across 23 countries. The short ZTPI scales are reliable for country-level analysis, whereas we recommend the use of the full scales for individual-level analysis. The short version of ZTPI will further promote integration of research in the time perspective domain in relation to many different psycho-social processes.

Rethinking the psychology of tyranny: The BBC prison study

This paper presents findings from the British Broadcasting Corporation (BBC) prison study - an experimental case study that examined the consequences of randomly dividing men into groups of prisoners and guards within a specially constructed institution over a period of 8 days. Unlike the prisoners, the guards failed to identify with their role. This made the guards reluctant to impose their authority and they were eventually overcome by the prisoners. Participants then established an egalitarian social system. When this proved unsustainable, moves to impose a tyrannical regime met with weakening resistance. Empirical and theoretical analysis addresses the conditions under which people identify with the groups to which they are assigned and the social, organizational, and clinical consequences of either doing so or failing to do so. On the basis of these findings, a new framework for understanding tyranny is outlined. This suggests that it is powerlessness and the failure of groups that makes tyranny psychologically acceptable.

On the degree of stability of measured hypnotizability over a 25-year period.

Conducted a longitudinal study of hypnotizability, as measured by the Stanford Hypnotic Susceptibility Scale, Form A, that yielded a relatively high degree of stability in hypnotic responsiveness over repeated testings spanning a 25-year period. The 50 Ss were retested in 1985, after tests when they were students, between 1958-1962 and again in 1970. The statistically significant stability coefficients were .64 (10-year retest), .82 (15-year retest), and .71 (25-year retest). The means did not change significantly, and the median change in the scores of individuals was only 1 point on the 12item scale. A set of score measures and their intercorrelations insufficient to resolve the issue of why stability occurs. The stability of hypnotizability over time compares favorably with that of other measures of individual differences.

The Past and Future of U.S. Prison Policy Twenty-Five Years After the Stanford Prison Experiment

In this article, the authors reflect on the lessons of their Stanford Prison Experiment, some 25 years after conducting it. They review the quarter century of change in criminal justice and correctional policies that has transpired since the Stanford Prison Experiment and then develop a series of reform-oriented proposals drawn from this and related studies on the power of social situations and institutional settings that can be applied to the current crisis in American corrections.

Testing Zimbardo's Stanford Time Perspective Inventory (STPI) - Short Form An Italian study

In the present study the psychometric properties of the Stanford Time Perspective Inventory (STPI - short version) are assessed in an Italian sample. Factorial analysis of STPI items was performed on 1507 respondents (965 women and 542 men). Results showed a clear correspondence between factorial components and a priori hypothesized dimensions by evidencing three factors (Future, Hedonistic Present, Fatalistic Present). Italian translation of the STPI indicates a fair degree of internal consistency and good metrological characteristics. The present results parallel those previously reported for an American sample. The present study, however, failed in evidencing the ‘Past’ as a factor in the factor structure. The results are discussed in terms of individual differences with respect to the relationships between demographic variables and temporal dimensions.

On the ethics of intervention in human psychological research: With special reference to the Stanford prison experiment

Research was conducted recently (August 14-21, 1971) in which subjects assumed the roles of ‘prisoner’ or ‘guard’ for an extended period of time within an experimentally devised mock prison setting on the Stanford University campus. The projected twoweek study had to be prematurely terminated when it became apparent that many of the ‘prisoners’ were in serious distress and many of the ‘guards’ were behaving in ways which brutalized and degraded their fellow subjects. In addition, the emerging reality of this role-playing situation was sufficiently compelling to influence virtually all those who operated within it to behave in ways appropriate to its demand characteristics, but inappropriate to their usual life roles and values; this included the research staff, faculty observers, a priest, lawyer, ex-convict, and relatives and friends of the subjects who visited the prison on several occasions (for details see Zimbardo, Banks, Haney and Jaffe, 1973; Haney, Banks and Zimbardo, 1973). This research represents one of the most extreme experimental demonstrations of the power of situational determinants in both shaping behaviour and predominating over personality, attitudes and individual values. As such it extends the conclusions from Stanley Milgram’s research on obedience to authority (1974). But the ethical concerns voiced over Milgram’s treatment of placing subject-teachers in a conflict situation where they believed (incorrectly) that they were hurting another person are even more pronounced in the present case. Volunteer prisoners suffered physical and psychological abuse hour after hour for days, while volunteer guards were exposed to the new self-knowledge that they enjoyed being powerful and had abused this power to make other human beings suffer. The intensity and duration of this suffering uniquely qualify the Stanford prison experiment for careful scrutiny of violations of the ethics of human experimentation. The plan of this article is to: (a) Give a synopsis of the experiment to familiarize the reader with its basic features; (b) summarize one set of critical arguments levelled