Exploring the Trust Induced by Nail Polish Color

Exploring the Trust Induced by Nail Polish Color Shi-Min Gong 1 ly07031985@hotmail.com The Graduate Institute of Design Science, Tatung University Wen-Yuan Lee 2 wylee@ttu.edu.tw Department of Media Design, Tatung University Abstract Current study aims to explore the emotion of trust induced by nail polish colors. Thirty-one observers were invited to take part in a psychophysical experiment. Twenty nail colors were provided in the experiment. Each observer was asked to assess the nail color on 8 emotional scales. The results showed that the trusted nail polish colors should be accepted and not frivolous. The models showed that reddish colors with high lightness and low chroma produced trusted colors. A purplish color with high lightness tended to be accepted colors. Olive and bluish colors with high lightness and high chroma were frivolous. Keywords: trust, color, emotion Introduction Females love to dress and takes care their outward appearance more than male. They take care of anything affecting their outward appearance, including their clothes, shoes, jewelry, hair style, make-up, and nail polish, seeking a perfect outward appearance. However, besides the great effort on outward appearance, the most important issue is how people perceived the outward appearance. Moreover, how to use the outward appearance to win people s trust is worthy to explore. In this study, the nail polish colors were studied to see the influence of nail color upon people s trust and other emotion response. Experimental plan The purpose of the current study is to explore the relationship between the emotional response of trust and nail polish colors. To do this, a psychophysical experiment was carried out. Thirty-one observers were invited to take part, including 15 males and 16 females with an average age of 24.9 years old. The observers were asked to assess the 20 nail colors on 8 emotion scales. Eight emotional scale were used, i.e., trust, disgust, surprise, appreciation, acceptance, interest, and frivolity, according to Plutchik s emotion model 1-2 together with sexy scale. Each scale had four intensity steps, i.e., extremely strong, strong, a little strong, and not at all.

In terms of color selection, eleven basic color terms purposed by Berlin and Kay 3 were used, including red, orange, yellow, green, blue, brown, purple, pink, white, black, and gray colors. These 11 colors were produced according to Lin et al 4-6. s basic color boundaries. Additionally, nine top sale nail colors from high street were involved. In total, 20 nail colors were used in the experiment, as shown in Figure 1. Each color was measured from monitor by a GretagMacbeth Eye-One. The CIELab values of each color were calculated under D65 and CIE 1931 standard colorimetric. The distribution of color samples on CIELab space are illustrated in Figure 2. In Figure 2(a), a*-axis and b*-axis represent the redness-greenness and yellowness-blueness attributes, respectively. In Figure 2(b), L-axis and C*-axis represent the lightness and chroma attributes, respectively. During the experiment, the observers were invited to a dark room to assess 20 nail color samples on 8 scales. The illuminating/viewing geometry is 0/0, as shown in Figure 3. The image of each nail color applied onto left hand was displayed on 19-inch monitor. The resolution was set in 1440 pixels by 900 pixels. The size of each image is 900 pixels by 900 pixels. The experimental samples were presented in a random order. Two nail colors were replicated in order to examine if the observers provide consistent judgments. Additionally, observer accuracy was examined, aiming to see the agreement between observers. In prior to the experiment, the monitor was calibrated by a GretagMacbeth Eye-One with D65 light source and the white level of monitor was 210 cd/m 2. Figure 1: The color samples used in the experiment.

(a) CIELab a*-b* diagram (b) CIELab L*-C* diagram Figure 2: The 20 colors in CIELab (a) a*-b* and (b) L*-C* diagram Figure 3: Experimental situation Results 3.1 Observer repeatability and accuracy The data collected from four-step categories on each scale were converted into numbers, the step of extremely strong was given 3, strong 2, a little strong 1, and not at all 0. In prior to analysis, the observer repeatability and accuracy were examined by RMS (root mean square). The former is to see whether the observers can repeat their judgment or not. The latter is to examine how well the individual observer agrees with the mean results. The RMS equation is give below: RMS 2 ( X Y ) For observer repeatability, Xi and Yi are initial data and replicated data, respectively. For observer accuracy, Xi and Yi are individual data and all observers average, respectively. n is the number of data. i n i

For RMS of 0, it represents a perfect agreement between two data array. (a) Observer repeatability (b) Observer accuracy Figure 4: RMS for observer repeatability and accuracy The results are illustrated in Figure 4. It can be seen that the observer repeatability was ranged between RMS of 0.43 and 1.25, as shown in Figure 4(a). And the observer accuracy was ranged between RMS of 0.64 and 1.25, as shown in Figure 4(b). This indicated that the observers in the experiment can provide consistent judgment and all the observers agree the mean results. 3.2 The relationship between emotions and colors To see the relationship between emotions and colors, the nail polish colors were arranged in order along each emotional scale, as shown in Figure 5. In this diagram, from left to right is respectively for trust, disgust, surprise, appreciation, acceptance, interest, sexy, and frivolity scales. The findings were summarized below. (1) Except sexy scale, pink and nude colors were found to be the most distinguishing colors on all the scales, i.e., both colors were trusted, appreciated, and accepted together with not disgusted, not surprised, not interesting, and not frivolous. (2) For trust emotion, nude color was appeared to be the most trusted color, followed by light pink, pale pinkish grey, and pink colors. Green color was found to be the most distrusted color, followed by yellow, purple, and black colors. (3) On disgust scale, dark gray color was appeared to be the most disgusted color, followed by black, yellow, and green colors. On the contrary, light pink, pink, nude, and orange colors were not disgusted. (4) For surprise emotion, yellow color was appeared to be the most surprised color, followed by green, blue, and orange colors. On the contrary, nude color, light pink, pale pinkish grey, and magenta colors were not surprised. (5) On appreciation scale, pink color was the most appreciated color, followed by nude, light pink and magenta colors. On the contrary, burgundy, dark gray, and black colors were not appreciated. (6) For acceptance scale, light pink color was the most accepted color, followed by nude, pink, and pale pinkish grey colors. On the contrary, green, dark gray, and yellow colors were not accepted.

(7) For interesting emotion, green color was the most interesting color, followed by yellow, light blue and orange colors. The most uninteresting color was nude color, followed by light pink, dark purple and black colors. (8) On sexy scale, vivid red color was the sexiest color, followed by red, magenta, and pink colors. On the contrary, green, dark gray, white, and yellow colors were not sexy. (9) For frivolity emotion, yellow color was the most frivolous color, followed by vivid red, green, and orange colors. On the contrary, light pink, nude, pale pinkish grey, and brown colors were not frivolous. Figure 5: The nail polish colors are ranked along affective feelings. 3.3 The correlation between emotions In order to understand the correlation between scales, the coefficient of correlation (r) was calculated. The results are given in Figure 6. In each diagram, each data point represents a nail polish color, The correlation coefficient and 45 line are also given in these diagrams to see how well they correlate with each other. The results showed that the highest correlation coefficient (-0.93) was found between disgust and appreciation emotions, as well as between disgust and acceptance emotions. Note that the correlation coefficients for these two pairs of emotions were negative, implying that the disgusted emotion are highly correlated with not appreciated and not accepted. It was also found that the emotions of surprise and interest are positively correlated with each other, the r value is 0.88. This implied that the influences of nail polish colors on the emotion of surprise were similar with those on interest. The same results were also found between the emotions of appreciation and acceptance.

The emotion of acceptance was found to be the most positively correlated emotion with trust (r=0.85), followed by appreciation (r=0.66.) On the contrary, the emotion of frivolity was found to be the most negatively correlated emotion with trust (r=- 0.82), followed by disgust (r=-0.81) and surprise (-0.77.) Furthermore, to see the relationship between the emotion of trust and other emotions, the multiple regression analysis was used. The emotion of trust was used as the dependent variable, other emotions as independent variables. The results are given in Eq 1. The correlation coefficient between predicted values and the trust emotion is also given in Eq 1. Trust =0.551 + 0.57Acceptance - 0.463Frivolity Eq 1: R=0.92 The results showed the performance of this regression model is well, indicated by the r value of 0.92. The emotion of trust can be modeled by acceptance and frivolity emotions. This model tell us that the trusted nail polish colors should be accepted and not to be frivolous. 3.4 The relationship between trust and color attributes As mentioned in previous section, the emotion of trust was evoked by acceptance and not frivolous. In this section, to see the relationship between trust and nail polish colors, the emotions of trust, acceptance, and frivolity were used as dependent variable. The color attributes were used as independent variables. The multiple regression analysis was used again. The color attributes used here included CIELab L*, C*, a*, b*, and h, representing lightness, chroma, redness-greenness, yellownessblueness, and hue angle, respectively. The results were shown in Eq 2 to 4. Trust = 0.476 + 0.012L* - 0.009C + 0.427cos (h) Eq 2 R = 0.83 The predictive performance of Eq 2 calculated by correlation coefficient (R) of 0.83 indicated this model can predict the results well. This model tells us that reddish colors with high lightness and low chroma can produced trusted colors, indicating a pink color. Acceptance = 0.744 + 0.012 L*+0.001 a* -0.002b*-0.004C+0.402cos(h) Eq 3 R = 0.77 The correlation coefficient of 0.77 in Eq 3 indicates this model can predict the results well. This model tells us that a purplish color with high lightness tended to be accepted, indicating a light purple color. Frivolity = 0.511+0.001L*-0.003a*+0.006b*+0.011 C-0.459 sin (h) Eq 4 R =0.90

The correlation coefficient of 0.90 in Eq 4 indicates this model can predict the results very well. This model shows that olive and bluish colors with high lightness and high chroma tended to be frivolous, indicating a vivid olive or a vivid blue color.

Figure 6: The correlation between emotion scales.

Conclusion The aim of current study is to explore the relationship between nail polish colors and the emotion of trust. A psychophysical experiment was carried out. Twenty nail polish colors were assessed on 8 emotion scale by 31 observers. The results showed that the trusted nail polish colors should be accepted and not frivolous. The models showed that reddish colors with high lightness and low chroma produced trusted colors. A purplish color with high lightness tended to be accepted colors. Olive and bluish colors with high lightness and high chroma were frivolous. The results assist us to understand the influence of appearance upon people. However, how person looks involve several attributes, such as skin color, clothes, shoes, and accessories. These appearance attributes are suggested to be involved in the future study to see the influence of total appearance. Acknowledgements This study is funded by the National Science Council in the Taiwan. The project number is NSC-100-2221-E-036-029-MY2. References 1. Plutchik R. Human emotions have deep evolutionary roots, a fact that may explain their complexity and provide tools for clinical practice. American Scientist, 2012;89:344-350. 2. Plutchik R. Emotion and life: perspectives from psychology, biology, and evolution. Washington, DC: American Psychological Association.; 2002. 3. Berlin B, Kay P. Basic Colour Terms: Their Universality and Evolution.: Basic Colour Terms: Their Universality and Evolution.; 1969. 4. Lin H, Luo M, LW M, AWS T. A Cross-Cultural Colour-Naming Study. Part III -- A Colour-Naming Model. Color Research and Application 2001;26:270-277. 5. Lin H, MR L, AWS T, LW M. A Cross-Cultural Colour-Naming Study: Part I- Using An Unconstrained Method.. Color Research and Application 2001;26:40-60. 6. Lin H, MR L, AWS T, LW M. A Cross-Cultural Colour-Naming Study: Part II- Using a Constrained Method.. Color Research and Application 2001;26:193-208.