The phychology of the "psi-conductive" experimenter: personality, attitudes towards psi, and personal psi experience

ABSTRACT

The experimenter effect, in which some experimenters are consistently more successful than other experimenters in obtaining evidence for psi, continues to be a major challenge for modern parapsychology. The term psi-conducive experimenter has been adopted to refer to a consistently "successful" experimenter, whereas an experimenter who has been consistently "unsuccessful" in obtaining psi effects is typically described as psi-inhibitory. Fifty researchers were identified who had acted as an experimenter in at least one published parapsychology experiment and who were likely to be able to be contacted by the author either in person or bye-mail. Of these, 40 completed and returned questionnaire booklets that included the Keirsey Temperament Sorter and a 6-item questionnaire asking about attitudes towards psi. They were also asked to indicate whether they had ever practised a mental discipline and whether they had ever had any personal psi experiences. Participants were also asked to rate the 50 named researchers according to whether they considered them to be psi-conducive or psi-inhibitory. Significant correlations were found between psi-conduciveness and belief in one's own ESP ability, belief in one's own PK ability, belief that ESP is possible, and belief that ESP can be demonstrated in an experiment.

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It has long been recognised that some experimenters in parapsychology appear to be consistently more successful than others in obtaining evidence for psi (e.g., Rhine & Pratt, 1957). This observation, referred to as the experimenter effect, recently led two researchers, Marilyn Schlitz and Richard Wiseman, one with a history of significant findings in support of psi (Schlitz) and one with a history of obtaining nonsignificant findings (Wiseman), to conduct studies under the same conditions. In two studies they found that data collected by Wiseman continued to be at a chance level, whereas Schlitz's data continued to show a significant deviation from chance expectation (Wiseman & Schlitz, 1997, 1999). The authors argued that the findings were unlikely to be explained in terms of randomisation artifacts, sensory leakage, participant cheating, or experimenter fraud. In addition, they treat as unlikely the possibility that Schlitz's participants were more "psychically gifted" than Wiseman's participants because o f the opportunistic way in which participants were assigned to experimenters. We are therefore left with the possibility that the differential findings are best explained by some undetermined differences between the two experimenters. For example, the two experimenters clearly have contrasting views regarding psi phenomena (we are told that whereas Schlitz is a "psi proponent," Wiseman is a "skeptic regarding the claims of parapsychology"). In addition, they differ in terms of both age and gender and are likely to differ to some extent in terms of personality.

One question, therefore, is which of these variables, if any, are helpful in predicting the likelihood of "success" as a psi experimenter? Following Parker (1977a, 1997b), experimenters who consistently obtain evidence in favour of the psi hypothesis are typically referred to as psi-conducive experimenters, whereas those who consistently do not obtain evidence in favour of psi have become labelled as psi-inhibitory experimenters. Although these labels refer to the outcomes of the experimenter's past research, they imply that psi-conduciveness is in some way linked to characteristics of the individual experimenter.

Such observations have led some researchers to examine more systematically those variables that may help distinguish apparently psi-conducive experimenters from psi-inhibitory experimenters. For example, Parker (1977a, 1977b) administered a personality factor questionnaire, the 16 PF, to American and European parapsychologists. Three judges (themselves psi researchers) classified respondents as either psi-conducive or psi-inhibitory according to their recently published experiments, which resulted in 15 psi-conducive and 14 psi-inhibitory experimenters being identified. On the basis of anecdotal reports of what makes a "successful" psi experimenter (see, e.g., Rhine, 1934/1973; Stanford, Zenhausern, Taylor, & Dwyer, 1975), it was predicted that psi-conducive experimenters would score higher than psi-inhibitory experimenters on dimensions of extraversion, warmth and sociability, confidence adequacy, and tenderness and sensitivity. However, no significant differences on any of these dimensions were obtained. A post hoc analysis of the other factors measured by the 16 PF revealed a tendency for psi-conducive experimenters to be more self-assertive and more intellectually sophisticated than psi-inhibitory experimenters.

In another study, students rated a number of parapsychologists against a list of 30 descriptive adjectives after watching video-recorded conference presentations by each one (Schmeidler & Maher, 1981a). Twenty-seven researchers' presentations at the 1979 Parapsychological Association Convention were video-recorded. From these, 5 psi-conducive and 5 psi-inhibitory researchers were selected who were matched in terms of age, sex, overt physical characteristics, and whether they grew up in the United States. Findings from both this study and an attempted replication (Edge & Farkash, 1992) found that the psi-conducive experimenters were generally rated as more enthusiastic, warmer, and less egoistic than experimenters classified as psi-inhibitory.

Thus, previous research has attempted to correlate psi-conduciveness with personality variables and how the experimenter is likely to be perceived by potential participants. The present study, conducted as part of a larger project on replication and experimenter effects in parapsychology aimed to build upon previous research on this topic in several ways. In contrast to anecdotal reports about the apparent importance of certain personality traits in being a successful psi experimenter, previous research examining the relationship between personality variables and psi-conduciveness has not revealed a clear relationship. Thus, in the present study, personality data were collected from a range of contemporary researchers who had conducted psi experiments. As such, this aspect of the study constituted a conceptual replication of Parker's (1977a, 1977b) study.

Second, whilst there has been much supposition about the importance of the experimenter's attitudes towards the phenomenon he or she is investigating (e.g., Palmer, 1986), there has been no attempt to systematically examine this hypothesis. Moreover, if, as is supposed, "successful" experimenters generally have more positive attitudes towards psi than "unsuccessful" experimenters, it is desirable to examine this in more detail. For example, Palmer (1971, 1972) has suggested that, in relation to the sheep-goat effect, participants' belief in ESP can be separated into a belief that psi exists in the abstract, a belief that psi could occur in the experiment, a belief in one's own psi ability, and how well one expected to perform in the experiment in which one was taking part. No previous research has attempted to assess the relative importance of these different aspects of the experimenter's attitudes towards psi in relation to the experimenter effect.

Third, the study sought to obtain ratings of psi-conduciveness for each of the researchers in the sample by asking each respondent to rate other named researchers on a psi-conduciveness scale. This procedure is useful in two ways. First, it makes it possible to assess the extent to which researchers agree or disagree about who is psi-conducive and who is not. If it reveals that there is very little agreement about who is, or is not, psi-conducive, then it would undermine the basic concept of there being identifiable psi-conducive and psi-inhibitory experimenters. This potential problem with classification was highlighted following Schmeidler and Maher's (1981a) study when one of the researchers originally labelled as psi-inhibitory was actually considered to be psi-conducive by two other parapsychologists (Schmeidler & Maher, 1981b). Second, assuming that there is, in fact, some agreement, it allows a mean psi-conduciveness rating to be calculated for each researcher. These mean ratings enable us to quantitat ively examine the extent to which psi-conduciveness can be predicted by other variables such as personality, attitudes towards psi, whether one practises a mental discipline, and whether one has had any personal psi experiences.

Fourth, whereas previous research has examined the role of different expenmenter variables in relation to experimental success separately, the present study was designed to examine the relative importance of age, gender, personality, attitudes towards psi, practise of a mental discipline, and personal psi experiences.

METHOD

Design

A correlational design was used in which age, gender, self-report measures of personality, attitudes towards psi, practise of a mental discipline, personal psi experience, and mean psi-conduciveness ratings (calculated from ratings given by all participants) were the variables.

Participants

Participants were researchers who had acted as an experimenter in at least one published parapsychology experiment. Fifty researchers were identified who were likely to be able to be contacted by the author either in person or by e-mail. To date, 48 of these have been contacted, of whom 43 agreed to provide data for the study. Of the 40 who completed and returned questionnaires, 29 were male and 11 were female (age range = 30-89 years, mean age = 52.0, SD = 14.19). The sample included researchers from the United States (n = 23, of whom 1 is currently based in the United Kingdom), the United Kingdom (n = 11, of whom 1 is currently based in Fiji), France (n = 1), Sweden (n = 1), the Netherlands (n = 1), Iceland (n = 1), India (n = 1, currently based in the United States), and Australia (n = 1).

Materials

A questionnaire booklet was compiled that consisted of six sections. Section A consisted of the 70-item Keirsey Temperament Sorter, which asked about the participant's personal preferences and how they generally behaved in different situations (Keirsey, 1998; Keirsey & Bates, 1984). This questionnaire is similar to the Myers-Briggs Type Indicator (MBTI) in that it is designed to measure personality according to jungian typology along the four dimensions: Extraverted-Introverted (E-I; 10 items), Thinking-Feeling (T-F; 20 items), Sensing-Intuitive (S-N; 20 items), and Judging-Perceiving (J-P; 20 items). The Keirsey Temperament Sorter was used in preference to the MBTI as it is shorter, is easy to administer, and has been shown to measure the same constructs as the MBTI (Tucker & Gillespie, 1993). For each item, responses are made by selecting which of two alternatives better describes oneself. Scores on the four personality dimensions measured by the Keirsey Temperament Sorter were calculated as follows: Those items on the E-I scale that were responded to in the direction of introversion were summed and subtracted from the number of items answered in the extroversion direction (scores could therefore range between -10 and 10, with more positive scores reflecting a tendency towards extraversion). Similar calculations were made for the S-N, T-F, and J-P dimensions (with scores ranging between a minimum of -20 and a maximum of 20, and positive scores reflecting a tendency towards Sensing, Thinking, and Judging types, respectively).

Section B included two questions. One asked about whether the participant practised any form of mental discipline (such as meditation), the other asked whether the participant had ever had an ostensibly "psychic" experience. "Yes" responses were coded as 1, "no" responses were coded as 0. If the participant answered yes to either of these questions, they were asked to give brief details.

Section C asked about the participant's thoughts about extrasensory perception (ESP) and psychokinesis (PK). Participants were asked to rate their agreement or disagreement with six statements: "ESP is possible"; "I have some ESP ability"; "It is possible to demonstrate ESP ability in an experimental study"; "PK is possible"; "I have some PK ability"; and "It is possible to demonstrate PK ability in an experimental study." Ratings were made using a 7-point scale where 1 = strongly disagree, 2 = moderately disagree, 3 = slightly disagree, 4 = neither agree nor disagree, 5 = slightly agree, 6 = moderately agree, and 7 = strongly agree.

Section D included three questions about how the participants conducted their experiments and their thoughts about the importance of replication in experimental research. (The data from these questions are to be reported in a separate article.)

Section E asked participants to rate 50 named psi researchers according to whether they considered them to be psi-conducive or psi-inhibitory. The 50 named individuals were those that comprised the participant sample. Ratings were made using a 7-point scale ranging from 1 (definitely psi-inhibitory) to 7 (definitely psi-conducive). The midpoint on the scale was labelled neither psi-conducive nor psi-inhibitory. For the purpose of this study, a psi-conducive experimenter was defined as someone who consistently obtains positive evidence for psi, whereas a psi-inhibitory experimenter was defined as someone who consistently does not obtain positive evidence for psi. If the participants felt unable to comment on any particular researcher (e.g., if they were not aware of any of the researcher's work), they were allowed to indicate this by ticking a "don't know" box.

A final section was included for any additional comments the participant wanted to make, either about the questionnaire or the issue of replication. Each section included brief instructions for how responses were to be made.

Procedure

Questionnaires were administered in person, via e-mail, or through the post between August 2001 and May 2002. Fourteen participants were administered questionnaires in person (of whom 12 were done so either at the conference of the Parapsychological Association in August 2001 or at the conference of the Society for Psychical Research in September 2001). The remaining participants were administered questionnaires via e-mail or through the post. In all cases, participants were told that the study was part of a larger project on experimenter effects and replication in parapsychology and that the aim of the study was to explore the relationship between a number of variables and psi-conduciveness as an experimenter, and that they would be asked to provide information about themselves as well as their perceptions of other researchers. They were also told that all the information they provided was anonymous and would be kept confidential. A consent form was attached to the front of the questionnaire booklet, which p articipants were asked to read and, if they consented, to sign. Participants were also asked to indicate their age and gender.

RESULTS

The 50 researchers were classified as psi-conducive, psi-inhibitory, or neither according to the ratings they received from their fellow researchers. Individuals were classified as psi-conducive if more than half of the ratings they received were in the range 5-7. They were classified as psi-inhibitory if they received mainly ratings of 1-3. and classified as neither if they received mainly ratings of 4. This procedure resulted in 41 psi-conducive researchers, 5 psi-inhibitory researchers, and 4 researchers classified as neither. To examine the level of agreement between respondents with respect to these classifications, a percentage agreement score was calculated for each researcher by dividing the number of ratings on which the classification was based (e.g., for psi-conducive experimenters the number of 5-7 ratings) by the total number of ratings they received, and multiplying by 100. Agreement levels for the 50 researchers ranged between 37% and 100%, revealing a high level of agreement (i.e., 70% agreeme nt or higher) for 23 researchers, a moderate level of agreement (50%-69% agreement) for 22 researchers, and a low level of agreement (lower than 50% agreement) for 5 researchers. There were very high levels of agreement (over 85% agreement) for just 16 researchers, of whom 13 were classified as psi-conducive and 3 were classified as psi-inhibitory.

To assess the relationship between psi-conduciveness and the other variables, a mean psi-conduciveness score was calculated for each participant by taking a mean of all the ratings they each received. Table 1 shows the correlations between psi-conduciveness scores and the other variables along with intercorrelations between all variables. Using a Bonferroni correction to correct for multiple analyses (i.e., replacing the alpha level of p = .05 with p = .0042), significant correlations remained between psi-conduciveness and belief in one's own ESP ability, r(40) = .66, p< .0005; belief in one's own PK ability, r(40) = .61, p< .0005; belief that ESP is possible, r(40) = .58, p < .0005; and belief that ESP can be demonstrated in an experiment, r(40) = .54, p < .0005. Suggestive correlations were found between psi-conduciveness and belief that PK is possible, r(40) = .37, p < .05, and the Thinking-Feeling dimension of the Keirsey Temperament Sorter, r(37) = -.33, p < .05.

Similar findings were obtained when these analyses were restricted to those participants for whom there was at least 70% agreement regarding their psi-conduciveness classification. With this restricted dataset, psi-conduciveness scores were significantly correlated with belief in one's own ESP ability, r(19) = .80, p< .0005; belief in one's own PKability, r(19) = .77, p < .0005; belief that ESP can be demonstrated in an experiment, r(19) .71, p = .001; and belief that ESP is possible, r(19) = .67, p = .002.

DISCUSSION

This study has revealed some important findings in relation to the concept of psi-conducive and psi-inhibitory experimenters. The psi-conduciveness ratings obtained in this study suggest that, in some cases, there is a range of opinions regarding whether an individual researcher is psi-conducive or psi-inhibitory. Of the 50 researchers included in the sample, 45 (90%) could be classified as psi-conducive, psi-inhibitory, or neither with at least moderate levels of agreement (i.e., over 50% agreement). Only 23 (46%) could be classified as either psi-conducive or psi-inhibitory with over 70% agreement. Not surprisingly, the greatest levels of agreement were observed for the small number of researchers who generally received very low or very high ratings. These data lend some support to the notion that psi-conducive experimenters can, in some cases, be distinguished from psi-inhibitory experimenters on the basis of their track record in conducting psi experiments. However, as was observed by Schmeidier and Maher (1981a, 1981b), some experimenters cannot be reliably classified in this way. This may be because experimenters may vary between being sometimes psi-conducive and at other times being psi-inhibitory. Such variability may be dependent on the type of psi task being used, the type of participants being tested, or to some other environmental factor.

There was a very strong tendency for researchers to be classified as psi-conducive (n = 41) as opposed to psi-inhibitory (n = 5). This pattern of ratings either suggests that researchers do tend to perceive the majority of their fellow researchers as psi-conducive or is better explained as a response bias caused by the nature of the scale used. For example, participants may have been biased towards giving ratings towards the higher end of the scale when rating experimenters who were not regarded as especially psi-conducive or psi-inhibitory in order to give such individuals the benefit of the doubt. Another possibility is that there really are fewer psi-inhibitory experimenters because those researchers who may have obtained null findings in their pilot studies simply decide not to conduct formal psi experiments.

Higher psi-conduciveness scores were most strongly associated with belief in one's own ESP and PK ability along with belief that ESP is possible and it is possible to demonstrate ESP in an experimental study. This suggests that it is these aspects of attitudes towards psi that are most important in predicting success as a psi experimenter (at least when success is measured by means of ratings by fellow researchers).

Owing to the correlational nature of the study, it is difficult to comment on the possible causal relationships between these variables. Indeed, it is likely that any causal relationships between psi- conduciveness and attitudes towards psi will be bidirectional. It may be that more positive attitudes to psi (and in particular a greater belief in one's own psi ability and belief that it is possible for psi to be demonstrated in an experimental study) result in being more successful in obtaining evidence in favour of psi. Such a causal relationship might be best explained in terms of one or more of the different models that are thought to explain experimenter effects. For example, one might choose to explain the relationship in terms of experimenter-participant interactions (in which the experimenter communicates his or her beliefs to the participants, thus affecting participants' motivation, beliefs, or expectations of success) or in terms of experimenter psi (essentially an experimenter sheep-goat effect). O ther models would explain the relationship in terms of the extent to which the experimenter attempts to adopt supposedly psi-conducive practices or procedures (the suggestion being that experimenters with more positive attitudes towards psi are more likely to make the effort to adopt such practices) or even in terms of experimenter error (the suggestion being that experiments conducted by psi proponents are methodologically flawed, thus resulting in spurious evidence of psi). In this regard, the strong relationship between self-perceived experimenter psi ability and psi-conduciveness found in the present study might be taken to provide indirect evidence for experimenter psi as the favoured interpretation of experimenter effects.

An experimenter's present attitudes towards psi may also be, at least in part, dependent on how successful the experimenter has been in the past. A history of obtaining positive evidence for psi is likely to have a positive impact on one's own attitudes towards psi, especially

one's thoughts about whether it is possible to demonstrate psi in an experimental study. Similarly, an experimenter who consistently does not obtain evidence for psi is likely to become less convinced of the reality of psi.

None of the personality variables, as measured by the Keirsey Temperament Sorter, were found to be significantly related to psi-conduciveness, suggesting that personality variables are relatively unimportant in being a successful psi experimenter. This is much the same as Parker (1977a, 1977b) found when using the 16 PF to measure personality. However, it should be noted that the Thinking-Feeling dimension of the Keirsey Temperament Sorter showed a suggestive correlation with psi-conduciveness, suggesting that there may be a small effect that would reach significance were a more substantial sample size available.

There is also little evidence that the practise of a mental discipline (such as meditation) and personal psi experience, though common amongst parapsychologists (66% of respondents noting a practise of a mental discipline, 79% having had a personal psi experience), are strong predictors of success as an experimenter. However, personal psi experiences may be an important factor in the development of researchers' beliefs about psi, especially beliefs about one's own psi ability.

The potential problems with the psi-conduciveness ratings must also be acknowledged. For example, in some cases, participants' ratings may have been partly based on whether they thought the person they were rating typically adopted psi-conducive practices in his or her experiments. In such cases, presumably where the participant was less sure of the researcher's track record, the term psi-conducive may therefore have been used in this way rather than to describe the researcher's history of experimental success.

In light of the findings from this study, further research may help to cast more light on the notion of psi-conducive and psi-inhibitory experimenters. For example, Palmer (1997) has suggested that these two groups of experimenters may be compared in how they typically interact with their participants in an experimental setting. Indeed, studies along these lines are being planned in which it is intended that these interactions will be videotaped for subsequent blind judging. Such studies may reveal important differences in the ways psi-conducive and psi-inhibitory experimenters interact with their participants. Because of the relatively small number of researchers who would be able to participate in such studies (especially, in light of the present study, researchers who can be reliably classified as psi-inhibitory), qualitative analyses of these experimenter participant interactions may be most appropriate. The potential utility of interviewing experimenters directly about how they conduct their experiments and how they interact with participants should also not be underestimated (Schlitz, 1987). Such interviews would also be able to address the issue of experimenters' attitudes towards psi, how their attitudes developed, and how they were affected by their experimental results.

A complementary approach is to experimentally manipulate experimenter expectancies about the success of an experimental procedure to examine the effect of such expectancies on participants' psi scores (e.g., Taddonio, 1976). The potential advantage of taking this approach is that it allows the possible causal effect of experimenter expectancy to be examined in more detail, not only on psi scores but also on how the experimenter interacts with participants. Again, studies adopting this approach are being planned.

TABLE 1

INTERCORRELATIONS BETWEEN ALL VARIABLES

Variable                             Sex         1       2 (b)  3 (b)

1. Age                             -.09 (a)
2. Extraverted-Introverted (E-I)    .49**(b)   .02 (c)
3. Sensing-Intuitive (I-N)         -.03 (b)    .18 (c)    .14
4. Thinking-Feeling (T-F)          -.19 (b)    .14 (c)    .05    .43
5. Judging-Perceiving (J-P)         .28 (b)    .12 (c)   -.02    .38*
6. Mental discipline               -.17 (b)   -.06 (a)   -.08   -.14
7. Personal psi experience          .03        .05 (a)    .07   -.35*
8. ESP is possible                 -.12        .19 (a)   -.26   -.25
9. I have ESP ability              -.10        .01 (a)    .07   -.27
10. It is possible to demonstrate  -.17        .21 (a)   -.23   -.11
    ESP in an experiment
    (ESP demo)
11. PK is possible                  .08        .34* (a)  -.20    .01
12. I have PK ability              -.05        .13  (a)  -.13   -.27
13. It is possible to demonstrate  -.09        .38* (a)  -.37*   .11
    PK in experiment
   (PK demo)
14. Psi-conduciveness               .11        .09 (b)    .08   -.15

Variable                           4 (b)  5 (b)  6       7        8

1.Age
2. Extraverted-Introverted (E-I)
3. Sensing-Intuitive (I-N)
4. Thinking-Feeling (T-F)
5.Judging-Percciving (J-P)          .40*
6. Menial discipline               -.04   -.36*
7. Personal psi experience         -.11   -.27    .45**
8. ESP is possible                 -.40*  -.16    .02     .15
9. I have ESP ability              -.28   -.38*   .40*    .53***  .51**
10. It is possible to demonstrate  -.28   -.06    .09     .11     .78***
    ESP in an experiment
    (ESP demo)
11. PKis possible                  -.13   -.04   -.01    -.02     .63***
12. I have PK ability              -.17   -.27    .18     .19     .40*
13. It is possible to demonstrate  -.06    .02    .01    -.06     .53***
    PK in experiment
   (PK demo)
14. Psi-conduciveness              -.33*  -.20    .29     .30     .58***

Variable                           9       10      11      12      13

1.Age
2. Extraverted-Introverted (E-I)
3. Sensing-Intuitive (I-N)
4. Thinking-Feeling (T-F)
5.Judging-Percciving (J-P)
6. Menial discipline
7. Personal psi experience
8. ESP is possible
9. I have ESP ability
10. It is possible to demonstrate  .45**
    ESP in an experiment
    (ESP demo)
11. PKis possible                  .22     .37*
12. I have PK ability              .54***  .25     .58***
13. It is possible to demonstrate  .14     .63***  .73***  .43*
    PK in experiment
   (PK demo)
14. Psi-conduciveness              .66***  .54***  .37*    .61***  .29

Note. Sex was coded 1 for male, 2 for female. Practise of a
mental discipline was coded as 0 for "no,"1 for "yes." Personal
psi experience was coded as 0 for "no," 1 for "yes." Unless
otherwise stated, N=40.

(a)N=36; (b)N=37; (c)N=33

* p<.05, ** p<.005. *** p<.0005.

(1.) Schmeidler (1997) has suggested that so-called "psi-conducive" experimenters should be further distinguished from "psi-permissive" experimenters.

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Psychology Department

Liverpool Hope University College

Hope Park, Liverpool L16 9JD

U.K

smithm3@hope.ac.uk

I would like to thank the Perrott-Warrick Fund for supporting this research. I am also greateful to those researchers who kindly completed questionnaires as part of this study, and to Michael Gordon, Carl Williams, and two anonymous reviewers for comments on an earlier draft of this article.

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