Effect of reward on subjective autonomy and interest when initial interest is low.
Clearly, in determining the effects of reward for task participation, the nature of the task is relevant. In interesting tasks rewards may decrease participants' interest, most reliably when rewards are expected, salient, and contingent on task engagement (Deci & Ryan, 1987). It has been hypothesized that when task interest is reduced in the presence of rewards, this occurs because rewards have reduced subjective autonomy. Humans are assumed to have a need to feel autonomous. As a means of behavior control, rewards are thought to reduce subjective autonomy, and reduction in subjective autonomy is believed to lead to loss of interest (Deci & Ryan, 1994).
Interesting tasks are often performed to achieve pleasure that is inherent in the task. The pleasurable consequences of performing the task are events that coexist with the reward, discounting external rewards as controlling factors (Kelley, 1972) as well as making rewards less salient. In a boring task, rewards are much more salient as means of behavior control than in an interesting task. If salience of reward is important in reducing subjective autonomy, it might be expected that the less interesting the task, the more a reward will reduce the acting person's sense of autonomy. In other words, because rewards exercise greater control and are more salient when a task is dull than when it is interesting; one might expect a greater reduction in subjective autonomy when boring tasks are rewarded than when interesting tasks are rewarded.
Rewards are, of course, only one of many sources of behavior control. Because subjects participating in experiments are normally instructed to engage in a task, an obvious source of control in this context is instructions. Being instructed to perform a task will by necessity affect a subject's feeling of autonomy in performing that task. However, the observation that being instructed to act may reduce one's sense of autonomy can be accepted without necessarily assuming that behavior control by way of rewards will reduce subjective autonomy. Indeed, the thought that extrinsic rewards should reduce people's sense of autonomy seems somewhat counterintuitive.
Consider the fact that working for no pay is slavery. A slave is not his own master, which means that a slave has little autonomy. Working for a salary is normally associated with a greater degree of autonomy. Thus, an increase, rather than a decrease in autonomy should be a likely finding when engagement in a boring task is rewarded. A test of this hypothesis requires, of course, that the effects of choice and rewards are separated.
Because variation in subjective autonomy has been claimed to affect task interest, the relation between these two variables is theoretically significant. In spite of this, the relationship between subjective autonomy and task interest has not previously been subjected to direct empirical testing. We performed a pilot study that did not indicate any such association. Furthermore, when rewards are offered in exchange for engagement in a boring task, depending on the circumstances, both incentive effects (Calder & Staw, 1975; Loveland & Olley, 1979), dissonance effects (Greenwald & Ronis, 1978), and reverse-incentive effects (Freedman, Cunningham, & Krismer, 1992) have been reported. Thus, we did not expect subjective autonomy and interest to be associated.
To test the hypothesis that rewards increase rather than decrease subjective autonomy, we asked participants to play with a puzzle that did not interest them very much, and we measured their subjective autonomy and interest in the puzzle. To separate the effects of reward from reduced autonomy caused by instructions, different groups of subjects performed the task with or without reward under choice and no-choice conditions. We expected that the promise of reward would increase subjective autonomy whether or not subjects had a choice to perform the required task.
Participants. The participants were 32 social science students and 1 member of the administrative staff at the University of Osio. Three participants were excluded from analysis because they discovered a hidden camera. This left a total of 30 participants, of which 7 were males and 23 were females. Participants' mean age was 25.9 years.
Materials. The study was conducted in a quiet room, containing four chairs, two tables, and a cupboard. A puzzle called "Gripple" (m-squared, inc., Baltimore, MD) was glued to the table in front of the participants. Gripple is a puzzle where sixteen numbered buttons, consisting of four different colors, are manipulated on a two-dimensional plane to form various patterns. Four magazines were lying on the adjacent table. Participants' behavior was recorded using a concealed miniature video camera (Panasonic WV-KS152), placed about 110 cm away from the subjects.
Procedure and instructions. Participants were randomly assigned to one of the three following conditions: "Choice + reward," "No choice + reward," and "No choice, no reward." These three conditions were chosen so as to contain two (choice + reward), one (no choice + reward), and no factors (no choice, no reward) that were expected to increase subjective autonomy.
Upon reporting to the waiting room, participants were taken to the experimental room, where their task was to play Gripple for 20 min. The first part of the instructions was the same for all participants:
You are going to take part in an experiment in which we are interested in the things that people think and feel during the performance of an everyday activity. Let me show you this puzzle, called Gripple. Gripple is a puzzle in which you can arrange different patterns by turning these platforms [experimenter demonstrates].
After the puzzle had been explained, and the participants had had a chance to get to know it for about 1 min, participants were asked in writing to indicate their interest in Gripple by marking a visual analog scale (VAS) - a line of 100 mm. The VAS has been shown to be valid, reliable, and simple to use in the measurement of subjective phenomena (Gift, 1989; Little & Penman, 1989, Miller & Ferris, 1993). The left end of the line was designated "Not at all interesting," and the right end was designated "Very interesting." A mark in the extreme left end of the scale was given a score of 0, a mark in the extreme right end a score of 100, and a mark 30 mm from the extreme left end a score of 30.
Subsequently, the following instructions were read to participants in the choice + reward condition:
What you choose to do in this room is totally up to you, except that you should not take out things that you may have brought with you. You can sit here and entertain yourself with the Gripple puzzle if you like. If you want to, you can read the magazines, but you do not have to do to anything at all. It is up to you. Your thoughts and feelings are the things that interest us, not what you do. Nevertheless, because it also interests us to see what significance a reward could have for your thoughts and feelings, you will, if you choose to play Gripple for 20 minutes, receive these three instant lottery tickets afterwards [experimenter shows participant the lottery tickets]. In case you do choose Gripple, it is not interesting to us whether you choose to form specific patterns or not. The point is to engage in an activity. But as I told you, we will be as interested if you do not choose Gripple.
Participants in the no choice + reward condition were instructed as follows:
Your task in this room is to play Gripple. For playing Gripple during the 20 minutes that the experiment will last, you will receive these three instant lottery tickets afterwards [experimenter shows participant the lottery tickets]. It is not interesting to us whether you choose to form specific patterns or not. The point is to engage in this activity.
Participants in the no choice, no reward condition were instructed as follows:
Your task in this room is to play Gripple. It is not interesting to us whether you choose to form specific patterns or not. The point is to engage in this activity.
Finally, all participants were told the following:
When the 20 minutes are over, you will be given some questions. Do you have any questions for me now?
Questions were answered by repeating relevant passages from the instructions.
Participants in the no choice + reward and no choice, no reward conditions were then asked to start playing Gripple, until the experimenter told them it was time to stop. Participants in the choice + reward condition were told to go ahead and do what they felt like doing.
During the experiment, the instant lottery tickets used as rewards were placed so as to be visible to the participants in the rewarded groups at all times. The total price of the three lottery tickets used as reward was 60 kroner (about $8.70 in US funds). The maximum amount to be won on one lottery ticket was 250,000 kroner (about $36,250). The price of each lottery ticket, and the maximum prize, were printed on the tickets in easily readable letters and digits.
After the participants had spent 20 min playing, the experimenter told them that the experiment was over, that he had to go and get the questionnaire, and would be back in 5 or 6 min. All participants were told to wait in the experimental room. To avoid an "inequity effect" that might undermine the possible undermining effect of extrinsic reward on the participants' interest in the puzzle (Deci, 1972), all participants received their instant lottery tickets after the free-choice period. Thus, participants in the rewarded groups were told not to take the instant lottery tickets at this point.
During the 6-min period that the experimenter stayed away, participants' behavior was surreptitiously registered by a video camera. After the experimenter's return, all participants were asked again to indicate their interest in Gripple in the same way as they had before they started playing. The participants were also requested to answer the following written question by marking a visual analog scale: "To what extent did you feel that it was your own choice whether to play Gripple or not during the experiment?" The left end was designated "Totally the experimenter's choice," and the right end "Totally my own choice." Webster's Third New International Dictionary (1966) defines "autonomy" as the state of being independent, free, and self-directing. The choice question was designed to measure that state subjectively. If one has the feeling that how one acts is "totally" one's own choice, one feels autonomous.
Participants' playing time during the free-choice period was measured from video tapes by a person blind to the experimental conditions. The playing time of the first eight participants (27%) was also measured by a second "blind" observer. The measurements made by the two observers correlated highly, [r.sub.s] = .81, p = .01.
Results and Discussion
Results from nonparametric tests are reported where some or all the data analyzed were found to depart significantly from a normal distribution, and/or were not sufficiently homogenous, even after data transformations. Because preliminary analyses yielded no gender effects, this variable was ignored in the reported analyses.
We hypothesized that a reward, as well as the possibility to choose, would increase participants' feeling of autonomy. Hence, the three experimental conditions contained two, one, and no factors, respectively, that should increase subjective autonomy. A one-way ANOVA exposed clear differences regarding the three groups' feeling of autonomy: Choice + reward: M = 80.9; no choice + reward: M = 67.5; no choice, no reward: M = 27.6, F(2, 27) = 7.64, p [less than] .01. Planned contrasts revealed that both choice + reward and the no choice + reward groups felt significantly more autonomous than the no reward group, t(27) = 3.76, p = .001, and t(27) = 2.81, p [less than] .01, respectively. Thus, these findings supported our predictions, though it should be noted that even if the difference between the two rewarded groups was in the predicted direction, this difference did not reach significance, t(27) = .94, p [greater than] .05.
As expected, no significant correlation was found between participants' subjective autonomy level and their expressed interest in Gripple, either before (r = -.07, p [greater than] .05) or after (r = -.1, p [greater than] .05) having played. There was also no significant correlation between subjective autonomy level and the number of seconds the participants played Gripple during the free-choice period, [r.sub.s] = .003, p [greater than] .05. These findings further strengthen the hypothesis that there is no link between subjective autonomy and interest in boring tasks.
Time actually spent playing during the period of unobtrusive observation is an alternative way of measuring task interest that is popular in research on reward effects with interesting tasks. A Kruskal-Wallis one-way ANOVA yielded no significant difference in the time the three groups spent playing Gripple during the free-choice period: Corrected for ties, H(2, N = 30) = .12, p [greater than] .05. However, the groups' mean playing times differed: Choice + reward: M = 56.3; no choice, no reward: M = 59.4; no choice + reward: M = 30.8. A planned Moses test of extreme reactions initially showed a significant difference between the free-choice playing time of the no choice, no reward group and the no choice + reward group, p (one-tailed) [less than] .05. However, after removing one outlier from each end, this difference was no longer significant, p (one-tailed) [greater than] .05. During the free-choice period, the mean time spent playing Gripple for all participants (N = 30) was 49 sec (SD = 97).
A one-way ANOVA did not reach significance with regard to differences in groups' reported interest in Gripple after having played, F(2, 27) = 2.72, p [greater than] .05. The groups' postexperimental interest scores and reported interest change from preplay to postplay are reported in Table 1. Before the experiment, the total mean interest score was 32.9. A one-way ANOVA revealed no difference between groups at this point, F(2, 27) = .13, p [greater than] .05. No significant correlation was found between the time participants spent playing Gripple during the free-choice period, and their expressed interest in Gripple, neither before ([r.sub.s] = .16, p [greater than] .05) nor after ([r.sub.s] = .18, p [greater than] .05) having played. However, preplay and postplay interest scores correlated significantly, r = .59, p = .001.
Mean Reported Postplay Interest and Change from Reported Preplay Interest
Postexperimental interest Change Group M SD M SD
Choice + reward 22.1 22.8 -7.7 28.2 No choice, no reward 38.3 17.1 3.1 17.2 No choice + reward 47.7 32.2 13.9 18.2
Note. The mean postplay interest score for the entire population was 36.0, SD = 26.3.
Although the above results clearly supported our hypotheses, some questions were also left without an answer. Experiment 1 showed that the promise of a reward increased subjective autonomy. Nevertheless, we suspected that this might not be the case if the reward was sufficiently low: When one engages in a boring task in exchange for a low reward, the low reward may signal that it is important to the experimenter that one chooses to play, so the reward will increase a sense of obligation, but not a sense of wanting very strongly to play. If this hypothesis is correct, a low reward should give rise to no more subjective autonomy than no reward.
On balance, when the reward is sufficiently high to be attractive, the reward may increase the feeling of autonomy because one oneself wants to play, as a means of obtaining the reward. If this assumption is correct, a high reward should give rise to more subjective autonomy than both no reward and a low reward. In the second experiment, we also wanted the opportunity to look at possible interaction effects between reward and choice, as well as the combination of choice and no reward.
Experiment 2 attempted to extend the findings from Experiment 1. To make sure that we were dealing with an uninteresting task, we included only participants who initially rated Gripple below 50 on the VAS, on which the maximum interest score is 100. Because the free-choice behavioral measure did not seem to yield important information for our purposes, it was not included. Participants were either given a choice or no choice with regard to playing Gripple. They received either no, low, or high reward.
Participants and materials. The participants were selected among 155 college students and office workers. Only participants who, after having familiarized themselves with Gripple, rated the puzzle below 50 on the 0 to 100 VAS interest scale were included in the experiment. This amounted to 118 persons. Among the 118 participants scoring below 50 on the interest scale, 17 of the participants allowed to choose chose not to engage in the target activity, a fact that will be discussed below. Also, 3 participants failed to act in accordance with instructions, and 1 participant guessed the true purpose of the experiment. None of these participants was included in the analysis. One participant was excluded because of experimenter error. Thus, data from 96 participants were included, 42 males and 54 females. Participants' mean age was 23.7 years. The materials were identical to those in Experiment 1.
Procedure and instructions. The subjects participated in a 2 (choice or instruction to play) x 3 (no reward, low reward, or high reward) design. Participants were randomly assigned to one of six conditions, termed "choice, no reward," "choice, low reward," "choice, high reward," "no choice, no reward," "no choice, low reward," or "no choice, high reward."
The initial instructions given to all participants were identical to those in Experiment 1. However, in the present experiment, participants were given more time to familiarize themselves with Gripple before indicating their initial interest in the puzzle on the VAS.
Subsequently, the two rewarded choice groups were given instructions identical to those given to the choice + reward group in Experiment 1, and the two rewarded groups that were instructed to play were given the same instructions as the no choice + reward group was given in Experiment 1, except for the fact that the choice, low reward and no choice, low reward groups were shown, and told about, only one 10-kroner (about $1.45) instant lottery ticket. The choice, no reward and no choice, no reward groups were given the same instructions as the rewarded choice and instruction groups, respectively, apart from the fact that unrewarded groups were not shown, or told about, any lottery tickets. All participants filled in the same questionnaire as that used in Experiment 1. Participants in rewarded groups received their lottery tickets after having finished filling in the postexperimental questionnaire.
Results and Discussion
Because preliminary analyses yielded no gender effects, this variable was ignored in the reported analyses.
Based on the initial hypothesis and the findings of Experiment 1, we expected that the promise of a high reward would increase participants' sense of autonomy relative to that of participants promised no reward or only a low reward. We also expected that participants given a choice would feel more autonomous than those instructed to play. All predictions were confirmed.
A choice x reward ANOVA yielded main effects on subjective autonomy of both the reward, F(2, 90) = 3.85, p [less than] .05, and choice factors, F(1, 90) = 19.26, p [less than] .001. No significant interaction effect was found. Planned contrasts showed that the no choice, high reward group reported higher subjective autonomy than the two other nonchoosing groups combined, t(90) = -2.47, p (one-tailed) [less than] .01, and the choice, high reward group reported higher subjective autonomy than the two other choosing groups combined, t(41) = -1.91, p (one-tailed) [less than] .05. Both among the three choosing groups and the three instructed groups, differences in mean subjective autonomy scores between the low reward groups and the two other groups did not reach significance.
This means, not surprisingly, that the groups given a choice felt more autonomous than those instructed to play. More interestingly, both among the three instructed groups and among the three groups allowed to choose, the high reward group felt significantly more autonomous than the two other groups combined [ILLUSTRATION FOR FIGURE 1 OMITTED]. Thus, the promise of reward did increase participants' sense of autonomy, but only when the reward was high.
No significant correlation was found between subjective autonomy level and expressed interest in Gripple, either before (r = -.05, p [greater than] .05) or after (r = .03, p [greater than] .05) having played. These results confirm and extend the findings from Experiment 1.
A choice x reward ANOVA yielded neither significant main effects nor interaction effects regarding postplay interest in Gripple. In spite of possible problems related to the use of change scores (Keppel & Zedeck, 1989), it should be mentioned here that the main effect of reward in a choice x reward ANOVA approached significance regarding preplay to postplay changes in Gripple interest, F(2, 90) = 2.8, p = .066.
All groups increased their expressed interest in Gripple as a result of playing with the puzzle (see Table 2). Before the experiment, the total mean interest score was 23.54. ANOVA revealed no difference between groups at this point.
Mean Postplay Interest and Change from Preplay Interest
Postexperimental interest Change Group M SD M SD
No choice, no reward 43.1 27.5 21.8 27.8 No choice, low reward 39.0 25.1 12.8 22.7 No choice, high reward 55.5 25.0 32.9 27.2 Choice, no reward 53.6 27.7 29.3 30.0 Choice, low reward 39.2 24.1 14.4 21.0 Choice, high reward 44.3 23.3 23.0 25.5
Note. The mean postplay interest score for the entire population was 45.8, SD = 25.7.
No significant correlation was found between degree of reward and postexperimental interest score, [r.sub.s] = .03, p [greater than] .05. However, preplay and postplay interest scores correlated significantly, r = .25, p [less than] .05.
Opting out. All participants who were instructed to play engaged in Gripple for the stipulated period. Seventeen selected participants who were given a choice decided not to play Gripple: 3 in the high reward group, 8 in the low reward group, and 6 in the no reward group. As in other studies where participants are allowed to choose, it is hard to see how this phenomenon could be avoided (Elliot & Devine, 1994; Leippe & Eisenstadt, 1994). However, there is reason to believe that none of the main conclusions drawn from the present study is threatened by this fact.
The participants who chose not to play had a lower preplay interest score (M = 17.17) than those who went on to play (M = 23.69), although the difference was not significant. Nonetheless, this difference in preplay interest scores may have affected the interest change scores of the three choice groups. However, as we have seen, the effect of the choice parameter on change in expressed interest was far from significant. Furthermore, it was not of any particular interest in the present experiment.
Subjective autonomy, in contrast, was an important dependent variable. In neither experiment did we find a significant correlation between any interest score and subjective autonomy. This fact indicates that a possible effect of opting out on interest change scores did not affect the autonomy scores. In addition, there is no obvious reason why the participants who chose not to play should have reported a higher or lower subjective autonomy than those who did play. Both playing and abstaining from playing required the participant to exercise autonomy and make a choice.
Also, an almost identical pattern of subjective autonomy scores appeared in (a) the groups instructed to play, in which all participants did play Gripple, and (b) in the groups allowed to choose. This argues against the possible effect of opting out on subjective autonomy scores in the choosing groups - an argument that is strengthened by the fact that the choice + reward group in Experiment 1, and the choice, high reward group in Experiment 2 had almost identical autonomy scores, M = 80.9 and M = 80.0, respectively. As we have seen, the reward in Experiment 1 was the same as the high reward in Experiment 2, and no participants opted out in Experiment 1. In any case, the present experiment was not designed to test whether people given a choice would feel more autonomous than those not allowed to choose. This we took to be highly likely a priori.
We have shown that when participants were promised a relatively high reward, $8.70 worth of instant lottery tickets for 20 min of engagement in a boring task, participants demonstrated a higher sense of autonomy relative to that of participants promised no reward, or a only a low reward, $1.45 worth of lottery tickets. Thus, at least when a task is boring, rewards do not decrease subjective autonomy.
Research on interesting tasks has shown that rewards that are expected, salient, and contingent on task engagement will most reliably undermine intrinsic motivation (Deci & Ryan, 1987). Since the cause of such undermining is hypothesized to be reduction of subjective autonomy, the rewards used in the present experiments were also expected, salient, and contingent on task engagement.
The present study further demonstrated a considerable difference between high and low reward with regard to effect on subjective autonomy. Therefore, in discussing the effects of reward on autonomy, one should clearly differentiate between high and low reward. This has not hitherto been the case in the literature.
Our findings indicate that the effect of a high reward on subjective autonomy is not limited to situations analogous to the classic work situation, as when one is instructed to engage in a boring activity. High reward increases people's autonomy even when they choose to do a boring task, a situation more analogous to activities like domestic chores and certain types of academic activities. There is little in our results to indicate that subjective autonomy increases because the task in itself becomes more interesting. Rather, there is reason to assume that when participants were promised a sufficiently attractive reward, the sense of autonomy increased, because when one wants the reward, one wants to play, regardless of what the experimenter wants, because playing is perceived to be instrumental in producing the reward. Our hypothesis is that this made participants feel that the decision to play was theirs to a greater extent and consequently subjective autonomy increased.
Using a boring task, Deci, Eghrari, Patrick, and Leone (1994) reported a moderate, but significant, positive correlation between perceived choice and reported interest/enjoyment, but in neither experiment did we find a correlation between subjective autonomy and reported interest. The study of Deci et al. (1994) and the present experiments did not measure exactly the same subjective states, but these apparently inconsistent findings warrant further investigation.
In both our experiments, group differences in interest change failed to reach significance. However, in both experiments, no group had a higher interest score than the group that was instructed to play and received a high reward. This was also the case in a third experiment (Overskeid & Svartdal, 1994), where the task was moderately interesting. This finding is in accordance with data reported by Calder and Staw (1975). They found that task satisfaction increased after treatment in a group that was instructed to perform a task originally rated as low on intrinsic reinforcement, and received a relatively high reward. As in the present research, the reward was not contingent on achievement, but simply on task engagement. Loveland and Olley (1979), among others, have reported similar results.
With the exception of one group in Experiment 1, there was also a clear tendency for all groups in both experiments to increase their reported interest in Gripple. This finding should be interpreted in the light of research by Sansone, Weir, Harpster, and Morgan (1992), who found that participants tended to apply interest-increasing strategies when they engaged in a boring task they felt they should not quit.
In conclusion, our findings indicate that when reward-based attempts at increasing people's autonomy fail, the rewards themselves are not to blame, given that the "rewards" are valuable enough to feel rewarding to the rewarded persons. There are good reasons to suspect that a reward can only function as a reinforcer if it gives rise to positive emotion (Powell, 1987; Staats, 1975). An extension of that hypothesis can be formulated, based on the present findings: If a reward can reinforce behavior, it will also increase the feeling of autonomy.
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|Author:||Overskeid, Geir; Svartdal, Frode|
|Publication:||The Psychological Record|
|Date:||Mar 22, 1996|
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