The Influence of Self- and Partner-Enhancement, Perceptual Congruence and Personal Identity on Relational Satisfaction among Married Couples, Dating Couples and Same-Sex Roommate Dyads

This study builds on the Taylor and Brown theory of positive illusions to attain a more in-depth understanding of the relative influence of perceptual congruence and enhanced perception (positive illusions) on relational satisfaction. A sample of 812, organized into 406 subject-partner pairs of 203 married couples, 100 dating couples, and 103 same-sex roommate dyads completed questionnaires. Each subject rated him- or her-self on six personal qualities (social skills, emotional stability, agreeableness, hostility, depression, and spirituality) and four temperaments (Dominance, Influence, Supportiveness, Conscientiousness). Then they took tests that measured the same qualities to compare with the self-ratings. On another questionnaire, each partner rated the subject on the same 10 qualities. Both subjects and partners completed the Dyadic Adjustment Scale as the measure of relational satisfaction. Primary findings discovered that in most cases, positive illusions diminish relational satisfaction. The only setting in which benefit occurs is when partners rate subjects higher than subjects rate themselves. Congruence between ratings (whether subject-test, partner-test or subject-partner) is strongly associated with relational success. Findings contrast with the Taylor and Brown theory and provide a more nuanced look at the influence of enhancement or congruence.


Public significance statement
Positive illusions, the tendency to view self, others, or other phenomena more positively than objective criteria suggest, is common to the human experience. This study explores the impact of positive illusions in the context of personal relationships. How one views ones' partner (positive illusion or objectively) has important consequences on the success of that relationship.

The influence of self-and partner-enhancement, perceptual congruence and personal identity on relational satisfaction among married couples, dating couples and same-sex roommate dyads
When Taylor and Brown [1] presented research evidence that positive illusions-the belief that I rate higher in any given domain than objective evidence would suggesthave a beneficial influence on a person's life satisfaction, well-being, and relational success; heated debate followed. Early on Colvin and Block [2], Colvin et al. [3] were the primary antagonists questioning both Taylor and Brown's methodology and conclusions and went on to cite research that demonstrated the benefits of perceptual accuracy (e.g., [4,5]).
A good deal of research has provided support for the Taylor and Brown perspective (e.g., [6][7][8][9][10]), but other researchers have demonstrated the opposite. For instance, Robins and Beer [11] found that positive illusions may produce short term benefit but often result in long-term negative consequences. Other studies also demonstrated challenges with positive illusions and the benefits of greater accuracy of perception (e.g., [12][13][14][15][16]).
Since there appears to be evidence on both sides of the issue, this study attempts to unravel the dynamics of when illusion or accuracy produces better results. Baumeister [7] has already demonstrated that as the magnitude of illusion increases, the benefit diminishes. But we extend beyond Baumeister's efforts to explore a number of factors that may influence when illusion (or enhancement) is beneficial or harmful.
To accomplish this, three different types of ratings are employed: subject ratings, partner ratings and test results.
Subject ratings. The subjects rate themselves on six traits, four temperaments and 15 personal characteristics on 7-point scales.
Partner ratings. The partners rate the subjects on the same six traits, four temperaments and 15 personal characteristics on the same scale.
Tests. The subjects take personality or temperament tests (details provided later) that measure the six traits and four temperaments.
Then the influence of enhancement or congruence on relational satisfaction is explored. Specifically, the study addresses congruence or enhancement in three different settings: 1. Self-enhancement: do Subjects rate themselves higher than test results; 2. Partner-test enhancement: do the Partners rate the Subject higher than test results; and 3. Partner-Subject enhancement: do Partners rate the Subjects higher than the Subjects rate themselves.
We pause a moment to operationalize several terms or phrases. The term Subject (always capitalized) refers to the primary participant who self-rates on a number of qualities and then takes tests for comparison with the self-ratings. The Partner (always capitalized) refers to the other member of the dyad who assesses how he or she thinks the Subject rates on the same personal qualities. Enhancement refers to positive differences among test results, Subject ratings, and the Partner ratings. Deviation refers to the differences (absolute values) among the same three. The term relational satisfaction is the score on the Dyadic Adjustment Scale (DAS, [17]) and represents the primary dependent variable. To avoid redundancy we form two abbreviations: Subject RS and Partner RS.
A second issue explored is what George and George [18] call "essence qualities". It parallels Erikson's view of personal identity [19,20], but differs in that essence qualities identify specific areas in which an individual is heavily defined. In the questionnaire, 15 different personal qualities are Presented and Subjects rate to what extent they are defined by each of the 15 on 7-point scales. The Partners then rate the Subjects on the same 15 qualities.
The inclusion of essence qualities allows two additional types of exploration: First, since Subjects rate themselves and Partners rate the Subjects on essence qualities, contrasts between Subject-and Partner-ratings can be employed to measure the impact of these differences on relational satisfaction. This broadens the overall investigation to 25 different personal characteristics to test enhancement or congruence between Subjects and Partners Twenty-five is far more extensive than most studies in this area.
Second, the influence of the strength of essence qualities on relational satisfaction can also be measured. Linville [21] research allows some interesting parallels. She found that self-complexity has a significant positive impact on relational success and overall life satisfaction. It is anticipated that strength of essence qualities would have a similar effect.

Literature review
Positive illusions: do they exist and how are they measured. There is little controversy about the existence of positive illusions. The tendency to view one's self and important people in one's environment more positively than reality is common to the human experience (e.g., [1,[22][23][24][25][26]).
Several methods have been used to measure positive illusions: A common one is to measure one's self on a particular quality then measure hypothetical others on the same quality (e.g., [1,26,27]). In relationships, illusion may be measured by comparing an individual's perception with the perception of their partner (e.g., [9]). Lewinsohn et al. [28] contrasted the opinion of experts with the opinion of the subjects. In the objective world, there is often opportunity to compare with actual standards (e.g., [29]). Example: I think I'm really smart. A test reveals an IQ of 87. My perception is illusion. In the medical world, one's perception of likelihood or speed of recovery can also be contrasted with actual results (e.g., [26]). Example: A cancer patient thinks he will live another six months. He actually lives another four months. His opinion was illusion. In the present study we employ the method of research found in the objective domain: Self-perception is contrasted with results of an assessment instrument.
In addition to illusion about self, there is also a significant literature that deals with illusion about someone else. In the context of romantic relationships, the illusion applies to one's partner. The phrase "love is blind" dates back 650 years [30]. The meaning then and now is identical, and refers to the tendency to view one's partner with an unrealistically positive bias. Gagné and Lydon [31] and Solomon and Vazire [32] both address this phenomenon and argue that it is possible for one to have both positive bias and realistic appraisals of their romantic partner. In the present study, equal attention is devoted to both self-bias and partner-bias.
Positive illusions are associated with greater relational satisfaction. The logic of beneficial positive illusions was suggested by Bandura [33] who stated that if everyone viewed themselves entirely accurately they would only attempt tasks they could easily accomplish. Those who view themselves more positively often put in "the extra effort needed to surpass their ordinary performances" (p. 1176).
In addition to Taylor and Brown's work [1,26], Murray, Holmes and Griffin's [10] longitudinal research with a sample of dating couples revealed that good relationships were a combination of accepting certain negative qualities and idealizing (positive illusions) the strengths of their Partners. A year later, Murray and Holmes [9] included married couples into their study with similar results. Neff and Karney [34] and George et al. [35] found that people with higher relational satisfaction tend to see their Partners in a more positive light, to idealize their positive qualities and to view their own relationship as superior to others. Babincak [6] with a sample of 154 undergraduates found that those with an inflated view of themselves experienced greater personal and relational satisfaction. Morry, Reich, and Kito [8] found that with a sample of 92 cross-sex friendships, 90 dating couples and 94 married couples partner enhancement resulted in greater feelings of being understood, validated and overall relationship quality. This is only a sampling of an extensive literature on this topic (e.g., [36,37]).
Partner enhancement is associated with poorer relational satisfaction. The logic of a negative impact of a Partner having positive illusions about a Subject, is suggested by the marriage proposal. Many times, agreement to marry is concomitant with the rosy glow that renders inflated perception (positive illusions) of personal characteristics of their partner and ends down the line with divorce.
Robins and Beer [11] revealed that in personal relationships, positive illusions about one's partner may produce immediate happiness but result in long term diminishment of well-being, self-esteem and poorer relational success. Tucker and Anders [16] found that anxiously attached married men experienced poorer marital satisfaction due to their inability to accurately perceive their Partner's feelings. Cooper, Chassin, and Zeiss [13] found that congruence between the husband's self-concept and the wife's perception of the husband's self-concept was associated with greater relational satisfaction. An older study [15] found that greater relational satisfaction was associated with congruence between the husband's expectations and the wife's perception of those expectations.

Summary
The present research is exploratory. Since there is such a diversity of research outcomes in this field, hypotheses are difficult to form. What this study does contribute is a more objective assessment of enhancement or congruence by including comparisons with test results. Then, greater validity is achieved because of 25 personal qualities are used in these comparisons (see [48] for a discussion of these issues). Finally, the ability to include enhancement, congruence, diminishment, or deviation as predictors (of relational satisfaction) allows greater comprehensiveness.
The dependent variable is relational satisfaction as measured by the Dyadic Adjustment Scale (DAS). As mentioned earlier, subject relationship satisfaction is designated "Subject RS"; partner relationship satisfaction is designated "Partner RS". This study explores whether enhancement (Subject-test, Partner-test, Partner-Subject), congruence (Subject-test, Partner-test, Partner-Subject), deviation-the absolute value of differences between the same three contrasts, and strength of essence qualities has a significant impact on relational satisfaction. These comparisons are measured for the entire sample (N = 406) and for the three subsets of the sample: Married couples (N = 203), dating or engaged couples (N = 100) and same-sex roommates (N = 103).

Participants
A total of 812 subjects participated. They were assessed as dyads and were identified as the Subject and the Partner. Thus, there were 406 Subject-Partner pairs: 203 were married couples, 100 were dating or engaged couples, and 103 were same-sex roommates. The married couples were defined as legally married or cohabiting for at least one year. Dating and engaged couples were self-identified. Roommates were defined as living in the same dorm room or house and were restricted to same-sex roommates in a non-romantic relationship. All romantically involved couples were heterosexual.
Gender breakdown included 432 women (53%) and 380 men (47%). The ethnic composition of the group was 56% Caucasian, 11% Black, 11% Asian, 15% Hispanic and 7% other. The mean age of the married couples was 43.1 years (range 21-85); mean age of the dating/engaged couples was 25.1 years (range 18-59) and the mean age of roommates was 22.8 (range 18-61). Other demographics included religious affiliation, amount of education, and duration of the relationship. Married couples averaged: 3.4 years of college and 16.7 years married (range: 2-47 years). Dating couples: 2.6 years of college, 2.0 years dating (range: 1 month -5 years). Same-sex roommates: 2.6 years of college, 1.6 years as roommates (range: 1 month -3.4 years).

Materials
Materials included separate questionnaires for the Subjects and the Partners. The Subject questionnaire was four pages (2-sided) and the Partner questionnaire was two pages (2-sided). The questionnaires were identical for married and dating/engaged couples. They were also identical for roommates except for the relationship-satisfaction questions, which were adapted to measure satisfaction in the context of a non-romantic relationship.
The questionnaires. The Subject questionnaire began with 2/3 page of instructions, including the sponsoring organization, brief description of the study, assurance of confidentiality, informed consent, debriefing and further instructions about how to complete the hardcopy or the online versions. This was followed by six demographic items, 18 items that measured Essence Qualities, 10 items that allowed Subjects to make a self-rating on each of 10 personal qualities, and 60 items assessed social skills, agreeableness, depression, hostility, emotional stability and spirituality. Next followed a 24-item test adapted from the DISC that measured temperament types, and the final page measured relationship satisfaction with the Dyadic Adjustment Scale (DAS, [17]).
The Partner questionnaire included the same instructions and the demographic items. However, for the 18 Essence Qualities, the six personality measures, and the four DISC temperament measure, rather than rating themselves, they rated the Subject. The Partner questionnaire concluded with the Dyadic Adjustment Scale (DAS) to measure their own relational satisfaction.

Procedure
Students from an undergraduate research-methods class at a university in Central Alberta, collected data for partial class credit. They were provided with a script to use when approaching potential participants. The method of approach included face-to-face, telephone, email, and a variety of social media resourcesalways using the pre-prepared script.
Two different methods of assessment were used: Hard-copy and online versions of the questionnaire: 180 dyads completed the hard copy; 226 completed the online version. After hard-copy forms were completed, Subjects sealed the survey in a coded envelope and returned it to one of several collection boxes on campus. For online forms, when Subjects completed all questions, results were automatically forwarded to the central database.
All data were entered and analyzed. Irregular or incomplete forms were discarded prior to data entry. The most common type of discarded form was when one individual from the dyad responded but their Partner did not. More specifically, there were 812 valid forms. An additional 50 forms were discarded due to being incomplete or irregular. A depressing 292 forms were valid but were unpaired with a Partner and thus were unusable in the present study.

Variables
Overview. The study is complex and includes several different classes of variables and several types of analyses or manipulations of those variables. Because of this, the following road map will provide context. 2. The influence of three types of enhancement (Subject-test, Partner-test, Subject-Partner) on RS.
3. The influence of three types of deviation (Subject-test, Partner-test, and Subject-Partner) on RS.
4. The Profile Similarity Correlation (described later) computes the similarity of ratings among test results, Subject ratings, and Partner ratings. Demographics. Included are gender, ethnicity (Black, White, Asian, Hispanic, Other), age, religious affiliation (several prominent Protestant denominations, Catholic, agnostic, atheist, other) amount of education (scale ranging from less than high school to doctorate), and duration of the relationship.
The self-ratings. Subjects were asked to rate themselves on the six personal qualities: agreeableness, emotional stability, social skills, spirituality, depressiveness, and hostility and the four DISC temperaments: Dominant, Influencer, Supportive, Conscientious. Each of the self-ratings was scored on a 7-point scale. For trait measures, the upper and lower anchors varied based on the qualities being measured. The middle score was 4 (about as much as others) or an equivalent phrase. For temperament measures, the anchors were identical: 1 (not in the slightest) to 7 (yes, that's me!).
Appreciate that a self-rating on a trait is attempting to measure a single quality. Temperament, by contrast, is multi-faceted and statements appear to be not only double-barreled, but multi-barreled. The unique value of temperament measures (in a counseling or seminar context) and the difficulty of measuring these constructs for use in research, is fully appreciated. Because of this, the temperament measures see only limited use in this study. Two examples follow: Personality trait measures from assessment instruments. The choice of the six traits was based on the experience of the authors and their colleagues in a counseling context. All six personality variables have demonstrated their influence in the success and non-success of relationships. All variables produced a final measure ranging from 1 to 7 with 1 representing low levels of a particular quality and 7 associated with high levels.
Spirituality. Personal spirituality was assessed by 12 questions selected from the 18-item George-Mabb-Walsh Spirituality Scale [49]. All questions were measured on 7-point scales; anchors varied depending on the nature of the question. Three of the items were reverse coded. The final spirituality measure was the mean of the 12 items with 1 representing low levels of spirituality and 7 high levels.
Agreeableness, Emotional stability. Two predictors were selected from the Big Five Personality Inventory [50]: Agreeableness (9 items) and Neuroticism/emotional stability (8 items) were rated on 7-point scales that ranged from 1 (Strongly disagree), to 4 (Neutral) and 7 (strongly agree). The final measure for both variables was the mean of the relevant items.
Social Skills. Social skills was measured by 11 questions selected from the Carlsmith Social Skills Scale [40]. Items were rated on 7-point scales. Anchors varied based on the nature of the questions. Three of the items were reverse coded. The final measure was the mean of the 11 ratings.
Depression. Depression was assessed by 11 statements that measured depression from the Anxiety and Stress Scale [47]. Scales, scoring and the final measure were identical to those for Social skills. Thus, 1 represents low levels of depression and 7 high levels.
Hostility. Hostility was measured with 10 items selected from the State Hostility Scale [46]. Subjects indicated to what extent they agreed or disagreed with each of ten statements. Each statement was scored on a 7-point scale with the same anchors as those used in the Big 5. The final Hostility measure was the mean of the 10 items with 1 representing low levels of hostility and 7 indicating high levels.
DISC Temperament Scale measures. Four temperament qualities were assessed by an adaptation of an on-line version of the DISC Temperament Scale. Each of the four temperaments is associated with one of the four letters of D-I-S-C (Dominant, Influencer, Supportive, Conscientious). For instance, the description of the S (supportive) temperament is "I am cooperative, kind, loyal, patient, and enjoy encouraging and supporting others." The DISC assessment instrument included 24 lines of four randomly distributed words. In each line one of the words reflected the D (dominant) perspective; one of the words was associated with I (influencer); one with S (supportive) and the fourth word related to C (conscientious). Participants selected one word in each of the 24 sets. The raw score for D, I, S, and C was the sum of words that were circled. For this data set, D-scores ranged from 0 to 20; I-scores from 0 to 16; S-scores from 0 to 17; and C-scores from 0 to 17. To create metrics similar to other variables, raw scores were converted to 7-point scales based on a normal distribution of values utilizing the IBM SPSS® "Rv.Lnormal" procedure.
Essence qualities. Essence Qualities were assessed by Subjects rating to what extent 15 different attributes, widely found to be common defining qualities [18], were central to their identity. The items included: understanding, social, perceptive, generous, cherish family and family events, love of learning, deeply spiritual, ever growing, creative, disciplined, neat and orderly, musical, logical, and enthusiastic pursuit of fitness. The 15th item asked their profession and three additional lines were provided to include other options. These additional lines were heavily used as 67% of participants included at least one additional quality; 39% identified three additional qualities. All 18 items were rated on 7-point scales. The lower and middle anchors varied based on the quality described. The high anchor was 7 (central to my identity) for all 18. An example follows: 1. Disciplined. 1 (follow my urges), 4 (when necessary), 7 (central to my identity).
To reduce bias, the Partners also rated the Subjects on the same 15 measures. The final measure of the strength of each of the 15 Essence Qualities was the mean of the Subject's and the Partner's rating. This "criss-cross" method of reducing bias is widely employed in couples' research (see [51]). The overall measure was the mean of the 15 criss-crossed scores. A score near 1 represents many low ratings across the 15 contrasting qualities; a score near 7 indicates many high ratings across these diverse qualities. The variable being measured is: "To what extent am I heavily defined across a number of contrasting qualities." Relational satisfaction, the primary dependent variable. Relational satisfaction was assessed by the Dyadic Adjustment Scale (DAS, [17]) and was scored in the manner specified by the authors. For the roommates (in non-romantic relationships), some of the questions did not fit their setting, such as "quality of sexual relationships." Because of this, three of the 32 questions were deleted and one was adapted to better reflect a roommate setting (instead of "likelihood of divorce or separation," roommates' version was "likelihood of finding another roommate").
Both Subjects and Partners completed the Dyadic Adjustment Scale (DAS) so the study could assess how different variables influenced both the Subjects' relational satisfaction (Subject RS) and the Partners' relational satisfaction (Partner RS).

Difference scores
Enhancement measures. The measures of enhancement and congruence in the present study involved difference scores. These differences were calculated between (a) Subject self-ratings and test results (to measure self-enhancement), (b) Partner's ratings of the Subject and test results (to measure Partner enhancement), and (c) Partner's rating and the Subject's rating (to measure whether Partners rated Subjects higher than Subjects rated themselves). Also included was (d) Essence qualities. Since there were only Subject and Partner ratings only Partner-Subject enhancement could be measured Once differences were calculated, they were changed to z scores to create metrics similar to other variables. Correlations or regressions between the difference scores and relational satisfaction identified whether enhancement benefits, had no effect, or diminishes relational satisfaction.
Congruence measures. There were also four different congruence measures. The congruence measures are simply the absolute value of the four types of enhancement measures listed above. Congruence measures assessed to what extent participants deviated from congruence either with test scores or with the Subject self-ratings. A score near zero suggests high congruence whereas larger scores suggest deviation from congruence-whether enhancement or diminishment.

Profile similarity correlation
The Profile Similarity Correlation measure is increasingly used in couples' research (e.g., [52,53]) but shows promise as a tool to better understand the dynamics of relational satisfaction. The PSC is designed to measure similarity of profiles between two members of a dyad. In the present study, PSCs were computed across 10 variables, the six personality variables and the four temperaments.
Four PSC measures were computed in the present study: (a) the correlations between the Subject's 10 self-ratings and the Subject's test results; (b) the correlation between the Partner's 10 Subject-ratings and the Subject's test results; (c) the correlation between the Partner's 10 Subject-ratings and the Subject's self-ratings; and (d) the correlation between Subject's ratings of 15 Essence Qualities and the Partner's rating of the Subject's 15 Essence Qualities.
An example illustrates the usefulness of PSC. Let us say the Subject rates himself 4 s and 5 s on the 10 of the Essence Qualities and 1 s and 2 s on the other five. A hypothetical Partner rates the Subject 5 s and 6 s on the same 10 Essence Qualities and 2 s and 3 s on the other five. This profile illustrates two separate outcomes: Enhancement of the Subject by the Partner (the Partner consistently rates the Subject higher than the Subject rates himself) and a strong correlation between the two sets of values (a high PSC) due to the similarity of profile (high and low ratings by the Subject are matched by high and low ratings by the Partner).
If correlations between PSC and relational satisfaction are computed, a high correlation suggests that similarity of ratings is associated with relational satisfaction.

Results
The primary purpose of the study is to determine the influence of enhancement, congruence or diminishment on relational satisfaction among couples. In addition, we explore some related findings such as the influence of personal qualities and strength of Essence Qualities on relational satisfaction. We begin by reporting the psychometric validity of our variables and comparing our results with Baumeister's.

Psychometrics
All the primary criterion and predictor variables displayed good to excellent psychometrics. Table 1 provides a complete assemblage of essentially all variables used in the study and includes standard psychometrics plus measures of internal consistency (α).
A comparison of the 360 (44%) participants who completed the hard-copy questionnaires with the 452 (56%) who completed the online version found few systematic differences between the two sets. The authors judged that the two groups were sufficiently similar to combine into a single data set.

Influence of degree of enhancement on relationship satisfaction
First, present results partially confirmed the Baumeister findings that more extreme illusions are less beneficial. However, there was only one setting where enhancement increased relational satisfaction: The Partner's RS was higher if the Partner rated the Subject higher than the Subject rated him or herself (r[404] = .21, p < .001). However when the squared term was added in a stepwise regression analysis, the benefit dropped off significantly as the enhancement becomes greater: β = −.19, R = .40, R 2 = .16, R 2 change = .024, F-change (1, 403) = 11.523, p = .001. See Figure 1 that illustrates a positive linear relationship and a negative curvilinear relationship.

Influence of enhancement on RS
A brief overview of the central issue now takes place. The degrees of freedom for all correlations is 404 unless otherwise specified. Self-enhancement diminished both the Subjects' (r = −.21, p < .001) and the Partners' (r = −.14, p = .005) RS. The Partner-test enhancement resulted in lower Subject RS (r = −.18, p < .001) and had no effect on Partner RS (r = .08, p = .10). The Partner-Subject enhancement showed no effect for Subjects (r = −.03, ns) and, the one instance of support for Taylor and Brown, enhanced RS for Partners (r = .21, p < .001). A different pattern emerged when considering enhancement of Essence Qualities. Since no instrument measures Essence Qualities, the only enhancement possibility is a comparison of Subject ratings on each of the 15 with the Partner rating of the Subjects' Essence Qualities. The results found that Partner-Subject EQ enhancement was associated with greater relational satisfaction for the Subject (r = .14, p = .005) and even more so for Partner (r = .34, p < .001). Greater detail may be found in Table 2. Thus, with the exception of Partner-Subject enhancement, there was a consistent pattern of enhancement being associated with lower relational satisfaction.

Influence of deviation on relational satisfaction
Recall that deviation from congruence is the absolute value of (a) subject minus test, (b) partner minus test, and (c) partner minus subject. A score of zero indicates no deviation whereas a larger score indicates greater deviation.
The Subject-test deviation was associated with poorer RS for the Subjects (r = −.15, p = .002) and the Partners (r = −.17, p = .001). The Partner-test deviation predicted lower RS for the Subjects (r = −.17, p = .001) and the Partners (r = −.16, p = .001). Partner-Subject deviation was associated with lower RS (marginal) for the Subjects (r = −.10, p = .056) and the Partners (r = −.12, p = .016). Finally Subject-Partner Essence-Quality deviation showed a similar trend: lower RS for the Subjects (r = −.13, p = .010) and the Partners (r = −.14, p = .007). While no results were particularly robust, there was a consistent pattern of deviation being associated with lower relational satisfaction. Table 2 contains additional detail on how Marrieds, Dating, and Roommates fared on the same comparisons.

Influence of profile similarity coefficient (PSC) on relational satisfaction
Profile Similarity Correlations (for the entire data set) included:   Partner-test PSC. A high PSC predicted greater Subject RS (r = .27, p < .001) and Partner RS (r = .34, p < .001). A similar pattern of significance emerged for all subsets.
Partner-Subject PSC. A high PSC predicted greater Subject RS (r = .31, p < .001) and Partner RS (r = .33, p < .001). A similar pattern emerged for all subsets except for dating couples.
Subject-Partner PSC for Essence Qualities. A high PSC predicted greater Subject RS (r = .11, p = .032) and Partner RS (r = .11, p = .035). Although results in the context of Essence Qualities are barely significant, the pattern is consistent with other PSC measures.
Thus in all four setting similarity of correlations (high PSC) is associated with greater relational satisfaction for both subjects and partners. See Table 2 for detail.

Influence of strength of essence qualities on personal characteristics and RS
The influence of Essence-Quality strength on relational satisfaction was consistent with Erikson's theory. Stronger Essence Qualities on the part of the primary Subject was associated with greater RS for both the Subjects (r = .30, p < .001) and even more so for the Partners (r = .37, p < .001). A similar pattern of results was observed for all subsets.

Influence of personal traits on relational satisfaction
Both Subjects' and Partners' relational satisfaction was enhanced if they were more emotionally stable, agreeable, socially skilled, and spiritual, and was diminished if they were more hostile or depressed. The r-values ranged from .22 to .43 for the Subjects; from .12 to .28 for the Partners (all significance values were p < .001). It is interesting to note that the pattern of relationships was the same for both Subjects and Partners but the effect for Subjects was more robust in every instance.

Insights from regression analysis
This data set is not primarily designed for regression analysis or structural equation modeling. The study addresses several specific factors associated with relational satisfaction and there is no intent for it to be comprehensive. The objective of the regressions in this setting is not so much to attain high R 2 values but rather to test the relative importance of the predictor variables and also partial correlations after other variables are accounted for.
Two analyses were conducted: the first included a criterion variable of Subject RS, the second a criterion variable of Partner RS. Predictors for both analyses included six discrepancy variables (the last six variables in Table 1), four PSC variables (subject-test, partner-test, subject partner, subject-partner essence qualities), essence qualities (single combined variable), and the six tested personality variables. For all analyses, Stepwise Multiple regression was conducted with a p to enter of .07 and a p to drop of .10. Note: Additional regressions were conducted with subsets of these variables; contact the first author for additional information.  Thus, three qualities significantly influenced both Subject and Partner relational satisfaction: Strength of essence qualities, congruence between subjects and partners on the ten self-and partner-ratings (Subject -Partner PSC), and the negative impact of hostility. Depression was the greatest single predictor (negative) of the subjects' relational satisfaction. The partner viewing the subject higher than subject self-ratings was the second-ranked predictor of the partners' relational satisfaction.

Other differences
Analysis of gender differences were remarkable more for the similarity between men and women than for any differences. When contrasting type of relationships, for both Subjects and Partners, dating couples had the greatest RS (Ms = 4.86, 4.85), marrieds were next (Ms = 4.71, 4.67), and roommates were lowest (Ms = 4.32, 4.37). All pairwise comparisons were significantly different (α = .05).

Discussion
As the discussion progresses, the reader is reminded of the overall perspective of this study. Taylor and Brown [1] research supported the benefits of positive illusions in many settings. Subsequent research has instances of support or non-support for the Taylor and Brown Theory. Present findings are discussed in the context of identifying the influence of enhancement or congruence on relational satisfaction in several contexts.

The influence of enhancement
Three types of enhancement are explored in this study: Subject-test, Partnertest, and Partner-Subject. In contrast with the Taylor and Brown theory in almost all instances enhancement (positive illusions) is detrimental to relational satisfaction; both for the Subjects and the Partners. The only instance of support for Taylor and Brown is when Partners rate Subjects higher than Subjects rate themselves, the Partner's relational satisfaction is enhanced.
This pattern holds true for each of the subsets except for married couples. Their results are in the same direction but not significant for the Subject and show a non-significant positive trend for the Partner. The contrast of the married couples is perhaps in the nature of their relationship. In an on-going and committed relationship, researchers find that attention to (and even enhancement of) the positives and the ignoring of the negatives is one key to success in many marriages (see [9,34,35]).

The influence of deviation from accuracy of perception
For all three settings, a deviation from congruence from either the test results or the Subjects' self-ratings results in diminished relational satisfaction for both Subjects and Partners. When the Subject self-ratings deviate from the test results, the outcome is lower RS for Subjects and Partners and for each subset. An identical pattern occurs for deviation of the Partners' Subject-ratings with test results, also significant (for the entire sample). The results are less robust for the Partner deviating from Subject ratings. Both show negative impact but are barely significant. Although marrieds, dating and roommates show a similar pattern of results their outcomes are often do not achieve significance. The influence of PSC helps to create a more complete picture.

The influence of profile similarity correlation (PSC)
The Profile Similarity Correlation measures how similar (highly correlated) are the pattern of ratings between the couples on a given set of variables. Also, as suggested in the introduction, the PSC can also measure enhancement or diminishment.
The PSC produced some of the strongest results in the entire data set. For three of the PSC measures (Subject-test, Partner-test, and Partner-Subject), not only are benefits to the relational satisfaction of both Subjects and Partners for entire sample significant at the .001 level, most of the subsets achieve the same significance.
The message is clear. When the results of deviation from accuracy and the PSC are considered, one may say that relational satisfaction (whether for Subjects or Partners) is associated with reasonable accuracy of judgment and congruence with both the Subject self-ratings and test results. When the occasional benefit of enhancement occurs (only for the Partner rating the Subject higher than the Subject rates herself) one is motivated to ask the question: Is this the type of enhancement spoken of by Robins and Beer [11] that yields short-term benefit but long-term misfortune?

The influence of essence qualities
In the present study, those high in Essence Qualities scored a perfect record (all at ps < .001) of being more agreeable, emotionally stable, spiritual, better social skills, while being less hostile, and depressed.
The results were nearly as strong with the benefit on Subject's and Partner's RS. Of all possible correlations (between Essence Qualities and relational satisfaction), the effect was significant at the .001 level for the entire sample and all subset except dating couples.
These results, despite being robust, should not be that surprising. Erikson [19,20] anchored a strong personal identity (Stage 5) as the prerequisite to successful intimate relationships (Stage 6). Linville [21] also found emotional and relational health associated with her concept of self-complexity. The utility of essence qualities as a unique concept (despite similarities to Erikson and Linville) is their usefulness in a counseling or seminar context. George and George [18] have documented that almost never do a couple share identical essence qualities. In counseling, then, the couple can learn to enjoy the strength of shared essences and explore how to deal with essences that differ.

Variations based on the subsets
When considering the three primary subsets (marrieds, dating couples, roommates) responses were reasonably consistent with the overall results, except for the dating couples. Of 26 comparisons between the three groups, the dating couples produced similar but weaker results 16 times, completely opposite results 3 times, and were reasonably congruent results on the other six. Essentially, we found less influence on Subject and Partner RS by the dating couples than for the entire sample or the other two groups. Researchers speculate that the "in love" factor may be instrumental. "In love" is not an issue with the roommates and is less of a factor with the marrieds with an average duration of the relationships of 17 years. Perhaps the tendency of in-love Partners to idealize each other, renders the effects of enhancement, congruence or similarity to be not so great an influence. This also underlines the contention [18] that the dynamics of successful friendship (roommates in this case) are quite similar to the dynamics of successful romantic relationships.

Limitations of the study and conclusions
More might be done with the temperament measures. In this study, temperament was used only in the PSC correlations. The challenge of their multidimensionality provides difficulty for any researcher, but the multidimensionality is intrinsic to the concept of temperament. Their power in a counseling or seminar setting demonstrates that continued effort to provide effective ways to measure and employ them in research is desirable.
A possible solution is, perhaps, suggested by the measure of Essence Qualities in the present study. Essence Qualities are defined as contrasting qualities that define an individual. Yet a measure was derived "the mean of the 15" that measures strength of identity across a wide range of diverse qualities. Perhaps this provides some insights into the measure of temperament. Temperament should be easier to measure and conceptualize (than essence qualities) because the set of qualities are often highly correlated with each other.
Perhaps the greatest limitation of the study is that the areas in which enhancement or congruence were assessed (the six personality variables) is limited. There are thousands of areas in couple relationships that might also be assessed. How well do results from six variables extrapolate to enhancement or congruence across the wide array of other personal characteristics? Future studies might begin to systematically explore different classes of variables to gain a more complete picture.

A final word
The present study reveals that asking whether positive illusions are beneficial is too simplistic. The study appears to illustrate that positive illusions by the Partner may sometimes have benefit. But, this finding is overwhelmed by the weight of evidence that 1. assessment that is congruent with Subject ratings or test results, 2. assessment that does not deviate too far from the test or partner ratings, and 3. a high correlation between the perspectives of the one doing the judging and one being judged is beneficial to relational satisfaction.
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