• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Maximum Group Perceived Utility Consensus Models Considering Regret Aversion

    2022-05-09 07:00:08XUEYuqin薛雨沁CHENGDong

    XUE Yuqin(薛雨沁),CHENG Dong(程 棟)

    Glorious Sun School of Business and Management, Donghua University, Shanghai 200051, China

    Abstract: In the consensus-reaching process (CRP), the actual utility of decision-makers (DMs) is often influenced by the psychological behavior of regret aversion. However, the influence of regret aversion on DMs’ utilities is rarely taken into account in the existing consensus models. The consensus-reaching problem of DMs with regret aversion is explored to maximize their perceived utilities under a limited budget. Firstly, three basic types of perceived utility functions are constructed based on the regret theory to describe the perceived utility of DMs with various preferences. Then, considering the limited budget and individual regret aversion, the maximum perceived utility consensus models based on types of left-skewed, right-skewed, middle-skewed, and heterogeneous utility preferences are proposed to achieve the consensus that maximizes the group perceived utility. After that, an example of land-transfer price negotiation in China is given to illustrate the validity of the proposed models. Finally, the model comparison and the sensitivity analysis are presented to reveal the influence of DMs’ regret aversion on the CRP. The results suggest that the DMs’ regret aversion will not affect left-skewed and right-skewed groups, but will affect the consensus results of middle-skewed and heterogeneous groups.

    Key words: regret aversion; consensus model; interval preference; maximum perceived utility

    Introduction

    The consensus-reaching process (CRP) aims to draw on the opinions of all decision-makers (DMs) in a group so as to agglomerate agreement. It generally requires the assistance of a moderator, who uses cost compensation and other means to convince DMs to modify their opinions[1-2]. For the moderator’s interest, he/she always hopes to reach a consensus at the lowest cost, so the minimum cost consensus model (MCCM) is proposed[3-6]. Since the MCCM can improve consensus efficiency and reduce costs, it has been widely applied to various important group decision-making (GDM) issues, such as commercial negotiations, demolition compensation, and pollution control consultations[1]. However, the MCCM only considers the feelings of the moderator and ignores the effect of DMs’ utilities on the CRP[7-8]. Fully preserving the utility preferences of all DMs is the key to ensure the effectiveness of consensus opinion and its successful implementation in the GDM[9-10]. As the main body of the CRP, each DM hopes that his/her opinion will be given enough attention. In other words, the moderator needs to pay more attention to the utility of each DM, rather than just considering the compensation cost in the CRP. Therefore, the utility consensus models are required to be constructed in order to obtain the consensus that can be supported and satisfied by the DMs.

    Regret aversion, or the feeling of avoiding regret, is a common psychological phenomenon among DMs and may affect their utilities in the CRP[11-12]. Each DM will compare the consensus opinion with his/her own opinion, which may result in two kinds of psychology behavior: one is that the DM will feel regret if he/she finds that the individual opinion can better satisfy his/her preference than the consensus opinion; otherwise, he/she will feel joyful. When the DM anticipates the potential regret after the decision, his/her regret aversion will affect his/her decision to avoid making decisions that make him/her feel regretful. This expectation of regret or rejoicing about the decision results will affect both their utilities and opinions. The regret theory, proposed by Bell[13], and Loomes and Sugden[14], is used to measure the influence of the regret aversion on individual utility. In recent years, it has been successfully applied to GDM problems. For example, Zhouetal.[15]obtained the regret value of the alternatives by constructing a regret function to select the best alternative. Peng and Yang[16]took the DMs’ regret aversion and prospect preference into consideration, and proposed two algorithms to solve stochastic multi-criteria decision-making problem. These models work well to solve the GDM problem of alternative selection, but they pay little attention to the CRP, which usually reaches the consensus by means of an optimization method. Yang and Sen[17]built a multi-objective optimization model considering utility functions to obtain the best solution. Hoetal.[18]considered DMs’ utilities and risk attitudes, and proposed a fuzzy goal programming model in order to improve DMs’ satisfaction. Researchers[8-9]constructed the maximum utility consensus model based on linear and non-linear utility functions under limited budget constraints. Subsequently, based on the risk preference of DMs, Gongetal.[19]adopted piecewise linear utility functions to establish a utility consensus model so as to describe the dynamic preference and the consensus level.

    Maximum group perceived utility consensus models consider regret aversion of DMs. However, the psychology of DMs’ regret aversion is often neglected in the current utility consensus model, which uses the expected utility function to measure the DMs’ utilities. This may lead to the consensus result deviating from the solution recommendation obtained by applying the extant utility consensus theory. Therefore, it is necessary to consider the impact of DMs’ regret aversion when constructing the utility consensus model.

    This paper aims to explore how to obtain the optimal consensus that maximizes the group perceived utility considering DMs’ regret aversion. To portray the perceived utility of DMs with different psychological preferences, we first define three kinds of perceived utility functions based on regret theory, namely, left-skewed, right-skewed, and middle-skewed types. Then, the maximum group perceived utility consensus models under different preference structures are constructed, which improve and extend the current utility consensus theory. The main contributions of the study are as follows.

    (1) Considering the influence of DMs’ regret aversion, a consensus model of maximum group perceived utility under limited cost is proposed. Although Gongetal.[8]explored the problem of maximum group epxected utility consensus models for the first time, they did not consider DMs’ regret aversion.

    (2) Three types of perceived utility functions incorporating DMs’ regret aversion are defined. Compared with the expected utility function, this article is based on the regret theory to construct the perceived utility function to reflect the actual utility of the DM as much as possible.

    (3) The influence of different individual preference types of DMs on the CRP is explored. Based on the case of land transfer, this paper presents future work of solving the GDM problem with different DMs’ preference types by constructing a heterogeneous maximum perceived utility model. The results show that group members with different preference types tend to set a neutral land-transfer price, which is beneficial to the long-term cooperation between farmers and companies.

    The rest of this article is organized as follows. Section 1 describes in detail the research problem and explains the parameters to be used in the subsequent modeling. Section 2 focuses on the construction of three types of perceived utility functions based on regret theory. Then, four types of maximum group perceived utility consensus models are constructed in section 3. Section 4 gives an application example to verify the validity of the proposed models. To further illustrate the influence of regret aversion on the proposed consensus models, a comparative analysis and a sensitivity analysis are included in section 5. Finally, section 6 concludes the whole paper and presents the future work.

    1 Problem Description

    2 Construction of Perceived Utility Function Based on Regret Theory

    This section briefly introduces the knowledge related to regret theory, and then constructs three types of perceived utility functions accordingly: left-skewed, right-skewed, and middle-skewed regret utility functions. According to the individual perceived utility measurement formula, this section provides a basis for the following construction of the maximum group perceived utility consensus model.

    2.1 Regret theory

    The basic idea of regret theory is that the DM not only pays attention to the results that can be obtained from the selected option, but also compares the possible results under various options. When the DM finds that the results of choosing other options are better, he/she will feel regret. Otherwise, he/she will feel delighted. In regret theory, the perceived utility of the DM is composed of the expected utility function of the current result and the regret-rejoice function. Suppose that there are two decision resolutionsxandy, anduxanduyrepresent the expected utility value obtained by the decision resolutionsxandy, respectively. Then, the perceived utilityUxyobtained by the user for the decision resolutionxcan be expressed as

    Uxy=ux+R(ux-uy),

    (1)

    whereR(ux-uy) represents the regret-rejoice value generated by the DM who abandons the resolutionybecause of the choice of the resolutionx. Regret-rejoice functionR(ux-uy)is a monotonically increasing concave function, satisfyingR(0)=0,R′(ux-uy)>0, andR″(ux-uy)<0[21], which usually is presented as a negative exponential function formgR(ux-uy)[22]:

    gR(ux-uy)=1-exp[-δ(ux-uy)],

    (2)

    where the parameterδ∈[0, +∞] is the regret coefficient of the DM. The larger the value ofδis, the more impact of regret aversion on the DM will have.

    2.2 Construction of perceived utility function

    Considering the complexity of GDM, individuals prefer interval numbers to a crisp number to express their views more comprehensively. Unlike the crisp number, DMs often have different preferences for the values in the interval. In the CRP, the utility function is usually used to reflect the individual preference structure of DMs. According to different types of interval preferences, these functions are usually divided into left-skewed, right-skewed, and middle-skewed types[8]. The traditional utility functions only demonstrate the expected utility of DMs, which ignore the impact of DMs’ psychology on themselves and cannot reflect the real DMs’ utilities in the CRP. Therefore, the perceived utility functions are constructed to not only measure the impact of DMs’ regret aversion on utility, but also reflect the real utility as much as possible.

    We use the utility function in Gongetal.[8]to obtain the expected utility of three types of individual preference. A DM of a left-skewed type prefers the lower bound of his/her opinion interval, and his/her expected utility value will decrease with the increase of the opinion value.

    Definition1Letoibe the individual opinion value of the left-skewed DMdi, and then the perceived utility function ofdiis defined as

    (3)

    (4)

    Similarly, a DM belongs to the right-skewed type if he/she is inclined to the upper bound of the opinion interval and gains more utility when increasing the value of his/her opinion.

    Definition2Letoibe the individual opinion value of the right-skewed DMdi, and then his/her perceived utility function is defined as

    (5)

    (6)

    If the DM gains the largest utility when his/her individual opinion is equal to the median value of the opinion interval, his/her personal preference is called the middle-skewed type.
    Definition3Letoibe the individual opinion value of the middle-skewed DMdi, andΔκibe the utility difference between the consensus opinion and his/her opinion, and then the perceived utility function ofdiis defined as

    (7)

    Since the expected utility function of middle-skewed DMs is piecewise linear, we will discuss the utility difference caused by the comparison of consensus opinions and individual opinions in the following four situations.

    (8)

    (9)

    (10)

    (11)

    The utility difference reflects the closeness covering the individual opinion, the consensus opinion, and the median of the interval. When the utility difference is positive, the consensus opinion is closer to the median of the interval than the individual opinion. Otherwise, the individual opinion is closer than the consensus opinion to the median of the interval.

    3 Construction of Maximum Group Perceived Utility Consensus Models

    After constructing the perceived utility function based on the regret theory, three kinds of DMs’ perceived utilities can be obtained. On the base of section 2, this section will discuss the construction of homogeneous and heterogeneous maximum group perceived utility consensus models. Homogeneity means that DMs in the group have the same type of individual preference, while heterogeneity means that their preferences are not exactly the same. Considering DMs’ regret psychology and limited consensus budget, the maximum group perceived utility consensus models can be constructed based on homogeneous (left-skewed, right-skewed, and middle-skewed types) and heterogeneous utility preferences.

    3.1 Homogeneous maximum group perceived utility consensus model

    3.1.1 Left-skewedmaximumgroupperceivedutilityconsensusmodel

    When the DMs’ preferences are all left-skewed, the group can be defined as a left-skewed group. Based on the left-skewed regret perceived utility function defined in section 2.2, a left-skewed maximum group perceived utility consensus model under the constraints of limited cost and interval opinions is constructed.

    (12)

    Lemma1If the feasible region of a convex optimization problem is a continuous non-empty set, then there must be an optimal solution.

    ProofPlease refer to Ref. [23].

    Theorem1Left-skewed regret perceived utility model (12) is convex optimization and has an optimal solution.

    ProofThe standard form of the model is

    (13)

    (14)

    3.1.2 Right-skewedmaximumgroupperceivedutilityconsensusmodel

    If all DMs in the group belong to the same preference type with the right-skewed type, we call them a right-skewed group. Similar to section 3.1.1, the construction of right-skewed maximum group perceived utility consensus model is

    (15)

    Theorem2Right-skewed regret perceived utility model (15) is convex optimization and has an optimal solution.

    ProofThe standard form of the model is

    (16)

    which is similar to model (13). The proof that the inequality constraint is a convex function is the same as Theorem 1. Thus by proving that the objective function is convex, it is possible to prove that model (16) is convex optimization.

    (17)

    3.1.3 Middle-skewedmaximumgroupperceivedutilityconsensusmodel

    The middle-skewed group means that all the DM’s preference tends to the median of the interval. The construction of middle-skewed maximum group perceived utility consensus model is similar to section 3.1.1, which is constructed as follows.

    (18)

    Theorem3Middle-skewed maximum group perceived utility consensus model (18) is convex optimization and has an optimal solution.

    ProofThe standard form of the model is

    (19)

    which is similar to model (13). The proof that the inequality constraint is a convex function is the same as Theorem 1. Thus by proving that the objective function is convex, it is possible to prove that model (19) is convex optimization.

    (20)

    (21)

    (22)

    (23)

    3.2 Heterogeneous maximum group perceived utility consensus model

    In many practical decision-making issues, the goals of DMs are not always the same, which may result in their individual preference being different and often contradictory. The above three models only consider the situation of the single personal preference in the decision group, which is relatively simple and it is difficult to fully reflect the actual complex decision-making behavior. Therefore, the construction of maximum group perceived utility model in the situation of the various individual preferences is discussed in this section.

    The definition of a heterogeneous group is that the types of DMs’ personal preferences are not exactly the same and may be any of the left-skewed, the right-skewed and the middle-skewed types. Based on the three perceived utility functions, under the constraints of limited cost, a heterogeneous maximum group perceived utility consensus model is constructed.

    (24)

    4 Case Study of Land-Transfer Price Negotiation

    Since reform and opening up in 1978, China has experienced great economic growth and rapid urbanization. The ongoing economic development, and urbanization have been found to lead to land fragmentation in rural areas[25-26]. The fragmentation of rural land management not only affects mechanized operations, but also reduces production efficiency and increases production costs. To solve this problem, farmers are encouraged to transfer their land management rights, which is called land transfer, hoping to increase the utilization rate of land[27]. Many farmers are willing to circulate the land contract management right. To improve circulation efficiency and maintain sustainable land transfer, a proper land-transfer price is the core issue. Too low land-transfer prices may cause farmers to be unwilling to transfer their lands, while too high prices may cause contractors to be unwilling to contract the farmers’ lands. Therefore, the land-transfer price negotiation is an indispensable part during the transfer process. The land-transfer price negotiation usually involves the psychological expectations of government departments, contractors, farmers, and village committee members whose interests are closely related to the price. They have their own expected range for land-transfer price and their utility preferences are different. Contractors are left-skewed DMs, and they hope that the transfer price is as low as possible. Farmers are right-skewed DMs and hope that the transfer price is as high as possible. In order to promote rural land transfer, the village committee member always hopes that the transfer price is as moderate as possible, who is a middle-skewed DM. The government can be regarded as a moderator. If they fail to reach a consensus on the land-transfer price during the negotiation, it will be difficult to carry out land-transfer activities effectively. Therefore, how to coordinate the different utility preference types of contractors, farmers and village committee members on land-transfer price is a key issue related to the success or failure of rural land transfer. So, in this section four types of regret perceived utility consensus models proposed in the previous section are used to deal with rural land-transfer price problem, aiming to achieve the most suitable price for all of DMs.

    Suppose there are four DMs, {d1,d2,d3,d4}, whered1is a contractor,d2andd3are farmers, andd4is a village committee member. Liu and Han[28]used the rural land transfer price model to calculate the land-transfer price in Liaoning Province, Jiangsu Province, Hubei Province, and Sichuan Province reasonably. In 2016, among four regions, the highest circulation price was 150 RMB/(m2·d) and the lowest circulation price was 40 RMB/(m2·d). Based on this interval[40, 150], the initial opinion intervals of four DMs about the land-transfer price are generated randomly, which areo1=[54, 67],o2=[75, 90],o3=[60, 88], ando4=[40, 98].o′is the final land-transfer price. The unit subsidies that the government gives to four DMs arec1=15,c2=5,c3=5, andc4=2, respectively. In this instance, it is assumed that the weights of four DMs are equal, that is,w1=w2=w3=w4=0.25. The regret coefficient represents the degree of each DM’s regret aversion, of which the value range is [0, +∞]. For the convenience of calculation, the regret coefficient of four DMs is unified to be equal to random numbers within the interval, which isδ=1.5. Using the MCCM[8]for reference, the minimum cost is 40. Therefore, the limited cost budget in the model should be larger than the minimum consensus cost, and we takeB=50.

    In the case of land-transfer price negotiation, the decision group is a heterogeneous group, so the heterogeneous consensus model needs to be constructed. According to section 3.2, the maximum group perceived utility consensus model is as follows.

    (25)

    In order to demonstrate the feasibility of homogeneous consensus models, the values in the case are substituted into three types of proposed homogeneous models as a numerical example in the CRP.

    The left-skewed maximum group perceived utility consensus model is

    (26)

    The right-skewed maximum group perceived utility consensus model is

    (27)

    The middle-skewed maximum group perceived utility consensus model is

    (28)

    Using the Matlab optimization toolbox, the optimal solutions to the above models can be obtained (shown in Table 1). For a homogeneous group, the consensus opinion is determined by the group’s common utility preference. The left-skewed group has the smallest consensus opinion, while the right-skewed group has the largest one. For a heterogeneous group, the consensus opinion tends to the utility preference of the most similar DMs in the group. The heterogeneous group is composed of two farmers, a contractor and a village committee member. Among them, the number of farmers is the largest, and the land-transfer price is more in line with farmers’ left-skewed preference. The group perceived utility of the heterogeneous group is negative, representing the uncomfortable or painful feelings that the consensus opinion brings to the group.

    Table 1 Results of four types of maximum perceived utility consensus models

    5 Model Discussion

    5.1 Comparative analysis

    This section further analyzes the impact of DMs’ regret aversion on consensus. First, we construct the maximum utility consensus model without considering regret aversion in the same way as the maximum group perceived utility consensus model (see Appendix A). The only difference between these two models is that the utility constraint in the model not considering regret aversion obtains the expected utility rather than the perceived utility. Then the data in the example of land-transfer price negotiation are substituted into these models, and the results are shown in Table 2.

    Table 2 Results of the consensus model without considering regret aversion

    By comparing Table 1 and Table 2, we could obtain the following conclusions.

    (1) Regret avoidance psychology may make one DM feel regretful as well as joyful. For the left-skewed and the middle-skewed groups, the group perceived utility with considering regret (0.950 and 2.146, respectively) is greater than the expected utility without considering regret (0.791 and 1.929, respectively). At this time, most of DMs in the group are joyful. For the right-skewed and the heterogeneous groups, the group perceived utility with considering regret (0.129 and -0.080, respectively) is lower than the expected utility without considering regret (0.355 and 0.197, respectively) and most of DMs in the group feel regret for the consensus result.

    (2) The consensus of the middle-skewed and the heterogeneous groups affected by regret aversion will be slight, while the consensus of the left-skewed and the right-skewed groups will not be influenced. For a heterogeneous group composed of farmers, contractors, and village committee members, the regret aversion will make DMs pay attention to the type of preference of the minority in the group. In this instance, the contractor with the left-skewed preference is the minority in the group and prefers the price to be as low as possible. Therefore, the land-transfer price of the heterogeneous group considering regret aversion is lower than that without considering regret.

    5.2 Sensitivity analysis

    In this section, the cost and the regret coefficient of the DM are taken as variables, respectively. With other factors remaining unchanged, we will explore the impact of different costs and regret coefficients on the consensus results of four consensus models. The specific results of the impact on group perceived utility and consensus opinion are shown in Figs. 1 and 2, and the specific results of different regret coefficients are shown in Figs. 3 and 4.

    Fig. 1 Influence of budget on group perceived utility

    Fig. 2 Influence of budget on consensus opinion

    Fig. 3 Influence of regret coefficient on group perceived utility

    Fig. 4 Influence of regret coefficient on consensus opinion

    It can be seen from Fig. 2 that the movement direction of consensus opinions under the change of budget is related to the type of utility preference. For the left-skewed and the middle-skewed groups, the consensus opinion decreases with the increase of budget. While, for the right-skewed and the heterogeneous groups, the consensus opinion gradually increases. From Fig. 1, as budget changes, the increase or decrease of the group perceived utility level is independent of the type of utility preference. For four types of regret-perceived utility models, the group perceived utility increases with the increase of the budget. The larger budget the moderator gives, the more DMs can be compensated, and the group perceived utility will be greater.

    From Figs. 3 and 4, it can be found that the negative effect of regret has greater impact on the group perceived utility than the positive effect of rejoicing. With the increase of the regret coefficient, the impact of regret aversion will be greater. The perceived utilities of the left-skewed and the middle-skewed groups under the impact of rejoicing gradually increase, while the perceived utilities of the right-skewed and the heterogeneous groups gradually decrease. Also, the increase in perceived utility is significantly less than the decrease in utility. Moreover, the influence of the DMs’ regret aversion on the CRP is limited. When the regret coefficient increases to a certain level, the consensus opinion will no longer change.

    6 Conclusions

    Since the regret aversion of DMs has an important impact on the utility, the purpose of this study is to determine how to obtain the consensus opinion that maximizes the group perceived utility when considering regret aversion. Based on regret theory, three perceived utility functions are defined to obtain the perceived utility of DMs with different individual preference types. Then, under the constraint of limited cost, homogeneous and heterogeneous maximum group perceived utility consensus models are constructed based on perceived utility functions. The main conclusions are as follows.

    (1) For a homogeneous group, the consensus opinion is determined by common utility preference of the group. The left-skewed group has the smallest consensus opinion, while the right-skewed group has the largest one. For a heterogeneous group, the consensus opinion tends to the utility preference of the most similar DMs in the group.

    (2) The regret aversion brings both regret and rejoicing to the DMs. When most of the DMs in the group feel regret, the group perceived utility will be less than the expected utility of the group without considering the regret. Otherwise, the group perceived utility will be larger than the expected utility. Also, the negative effect produced by regret will have a greater impact on the group perceived utility than the positive effect produced by rejoicing.

    (3) The consensus of the middle-skewed and the heterogeneous groups affected by regret aversion will be more neutral, while the consensus of the left-skewed and the right-skewed groups will not be influenced. For a middle-skewed group, the consensus opinion and the individual opinion will be larger under the influence of regret aversion. For a heterogeneous group, the regret aversion will make DMs pay attention to the preference needs of the minority in the group. In the case of land-transfer price negotiation, the impact of regret aversion caused by different kinds of individual preferences will lead to a neutral land-transfer price, which helps to the long-term cooperation between farmers and companies.

    (4) As the compensation cost changes, the movement direction of consensus opinions is related to the type of group preferences, while the increase or decrease of the group utility level has nothing to do with the type of individual preferences. The consensus opinions of the left-skewed and the middle-skewed maximum group perceived utility consensus models decrease with the increase of the cost, while the consensus opinions of the right-skewed and the heterogeneous models increase. The group perceived utility of the above four types of models all gradually increase with the increase of the cost.

    Although this article provides a consensus method considering the bounded rationality of DMs, we assume that the regret coefficients of DMs are consistent, ignoring the impact of different perceptions of regret among individuals. Therefore, the maximum group perceived utility consensus model under different circumstances of regret coefficients is an interesting direction in future study.

    成年女人毛片免费观看观看9 | 欧美日本中文国产一区发布| 久久亚洲国产成人精品v| 日韩视频在线欧美| 深夜精品福利| av天堂在线播放| 日日爽夜夜爽网站| 亚洲欧美精品综合一区二区三区| 午夜两性在线视频| 久久久久久久精品精品| 国产精品三级大全| 天堂中文最新版在线下载| 观看av在线不卡| 国产成人免费观看mmmm| 国产成人啪精品午夜网站| 国产高清国产精品国产三级| 国产一区二区在线观看av| 日韩免费高清中文字幕av| 精品高清国产在线一区| 亚洲精品国产av成人精品| 免费一级毛片在线播放高清视频 | 99久久人妻综合| 亚洲国产最新在线播放| 国产精品欧美亚洲77777| 欧美人与性动交α欧美精品济南到| 亚洲一区二区三区欧美精品| 大香蕉久久成人网| 女人精品久久久久毛片| 2018国产大陆天天弄谢| 国产视频首页在线观看| 一级毛片女人18水好多 | a级片在线免费高清观看视频| 一本一本久久a久久精品综合妖精| 黄色视频不卡| 尾随美女入室| 国产福利在线免费观看视频| 国产片内射在线| 日韩 亚洲 欧美在线| 男人添女人高潮全过程视频| 日韩人妻精品一区2区三区| 成人三级做爰电影| 高清欧美精品videossex| 亚洲三区欧美一区| 99久久人妻综合| 侵犯人妻中文字幕一二三四区| 女性生殖器流出的白浆| 亚洲精品美女久久久久99蜜臀 | 亚洲人成电影免费在线| 久久久精品国产亚洲av高清涩受| 国产成人一区二区三区免费视频网站 | 国产在线一区二区三区精| 国产精品二区激情视频| 69精品国产乱码久久久| 亚洲 欧美一区二区三区| 蜜桃国产av成人99| 人人妻人人澡人人爽人人夜夜| 中文字幕人妻熟女乱码| 一本综合久久免费| 成年动漫av网址| 人成视频在线观看免费观看| 国产高清国产精品国产三级| 午夜视频精品福利| 最近中文字幕2019免费版| 国产成人91sexporn| 王馨瑶露胸无遮挡在线观看| videos熟女内射| 国产av精品麻豆| 桃花免费在线播放| 黄色视频在线播放观看不卡| 亚洲,欧美精品.| 汤姆久久久久久久影院中文字幕| 色视频在线一区二区三区| 另类精品久久| 午夜福利在线免费观看网站| 国产精品人妻久久久影院| 久久精品亚洲熟妇少妇任你| 亚洲视频免费观看视频| 麻豆国产av国片精品| 久久青草综合色| 国产高清视频在线播放一区 | 国产黄色免费在线视频| 欧美日韩视频高清一区二区三区二| 亚洲成人免费电影在线观看 | 久久国产亚洲av麻豆专区| 亚洲国产成人一精品久久久| 久久国产精品大桥未久av| e午夜精品久久久久久久| 一区二区三区乱码不卡18| 免费黄频网站在线观看国产| 亚洲欧美一区二区三区黑人| 国产高清videossex| 日韩一区二区三区影片| 19禁男女啪啪无遮挡网站| 欧美日韩一级在线毛片| 我要看黄色一级片免费的| 国产真人三级小视频在线观看| 纵有疾风起免费观看全集完整版| 国产人伦9x9x在线观看| 欧美亚洲日本最大视频资源| 国产熟女欧美一区二区| 777米奇影视久久| 欧美日韩av久久| 国产不卡av网站在线观看| 欧美日韩成人在线一区二区| 大片免费播放器 马上看| av在线app专区| 欧美xxⅹ黑人| 在线观看国产h片| 在线观看www视频免费| 久久久久精品人妻al黑| 99热网站在线观看| a级毛片黄视频| 国产又色又爽无遮挡免| 操出白浆在线播放| 老司机亚洲免费影院| 男女无遮挡免费网站观看| 中国美女看黄片| 黑人欧美特级aaaaaa片| 亚洲精品一区蜜桃| 亚洲激情五月婷婷啪啪| 黄色毛片三级朝国网站| 欧美97在线视频| 中文字幕人妻丝袜制服| 日韩av在线免费看完整版不卡| 免费不卡黄色视频| 欧美国产精品va在线观看不卡| 精品一区二区三卡| 成年人黄色毛片网站| 国产1区2区3区精品| 亚洲少妇的诱惑av| 日韩大码丰满熟妇| netflix在线观看网站| 丝袜喷水一区| 美女大奶头黄色视频| 在线观看国产h片| 成年动漫av网址| 丝袜人妻中文字幕| 99久久99久久久精品蜜桃| 久久久久久久大尺度免费视频| 男男h啪啪无遮挡| 欧美日韩视频精品一区| 成人国产av品久久久| 老司机亚洲免费影院| 亚洲专区国产一区二区| 18禁观看日本| 人妻 亚洲 视频| 人体艺术视频欧美日本| 香蕉国产在线看| 自拍欧美九色日韩亚洲蝌蚪91| 一区二区三区四区激情视频| 老司机在亚洲福利影院| 999久久久国产精品视频| av视频免费观看在线观看| 丝袜美腿诱惑在线| 久久精品久久久久久噜噜老黄| 日本猛色少妇xxxxx猛交久久| 50天的宝宝边吃奶边哭怎么回事| 国产爽快片一区二区三区| 香蕉丝袜av| 国产精品三级大全| 99久久人妻综合| 国产成人精品无人区| 国产日韩一区二区三区精品不卡| 自线自在国产av| 久久精品国产亚洲av高清一级| av一本久久久久| 亚洲五月色婷婷综合| 久久精品熟女亚洲av麻豆精品| 人妻一区二区av| 成年人午夜在线观看视频| 亚洲av综合色区一区| 男人添女人高潮全过程视频| 色网站视频免费| 久久性视频一级片| 亚洲精品日本国产第一区| 国产深夜福利视频在线观看| 99re6热这里在线精品视频| 国产精品成人在线| 国产精品三级大全| 美女国产高潮福利片在线看| 亚洲少妇的诱惑av| 90打野战视频偷拍视频| 日韩伦理黄色片| 亚洲国产精品一区三区| 日韩中文字幕欧美一区二区 | 午夜av观看不卡| 丰满迷人的少妇在线观看| 亚洲精品中文字幕在线视频| 纵有疾风起免费观看全集完整版| 高潮久久久久久久久久久不卡| 亚洲精品一区蜜桃| 两性夫妻黄色片| 丰满少妇做爰视频| 久久av网站| 色婷婷av一区二区三区视频| 激情视频va一区二区三区| 老司机影院毛片| 黑人猛操日本美女一级片| 国产爽快片一区二区三区| 伊人亚洲综合成人网| 免费在线观看日本一区| 国产av一区二区精品久久| 日韩伦理黄色片| 手机成人av网站| 亚洲中文av在线| av网站在线播放免费| 黄色 视频免费看| 国产av精品麻豆| 中国国产av一级| 亚洲精品一区蜜桃| 亚洲熟女精品中文字幕| 水蜜桃什么品种好| 成人亚洲欧美一区二区av| 一级片'在线观看视频| 下体分泌物呈黄色| 日韩精品免费视频一区二区三区| 黄色视频不卡| 香蕉国产在线看| 人人妻人人添人人爽欧美一区卜| 日本一区二区免费在线视频| 丁香六月欧美| 一区二区三区激情视频| 国产伦理片在线播放av一区| 欧美亚洲 丝袜 人妻 在线| 一边亲一边摸免费视频| 午夜福利视频精品| 国产日韩欧美视频二区| 久久天堂一区二区三区四区| 天天躁夜夜躁狠狠久久av| 1024视频免费在线观看| 中文精品一卡2卡3卡4更新| 在现免费观看毛片| 日本欧美视频一区| 亚洲欧美精品自产自拍| 性少妇av在线| 中文精品一卡2卡3卡4更新| 大型av网站在线播放| 51午夜福利影视在线观看| 欧美日韩一级在线毛片| 亚洲欧洲精品一区二区精品久久久| 欧美 亚洲 国产 日韩一| 欧美激情 高清一区二区三区| cao死你这个sao货| 日韩av免费高清视频| 欧美精品亚洲一区二区| 91精品三级在线观看| 各种免费的搞黄视频| 少妇 在线观看| 十八禁网站网址无遮挡| 亚洲七黄色美女视频| 国产精品三级大全| 婷婷成人精品国产| 亚洲国产欧美网| 丝袜在线中文字幕| 欧美激情高清一区二区三区| svipshipincom国产片| 少妇粗大呻吟视频| 精品国产乱码久久久久久男人| 色婷婷av一区二区三区视频| 不卡av一区二区三区| 18禁国产床啪视频网站| 一区二区av电影网| 色婷婷久久久亚洲欧美| 久久亚洲精品不卡| 久久99精品国语久久久| 免费在线观看日本一区| 久久精品国产a三级三级三级| 男女免费视频国产| 国产精品欧美亚洲77777| 国产精品免费视频内射| 热99久久久久精品小说推荐| 久久久精品国产亚洲av高清涩受| 美国免费a级毛片| 久久久精品免费免费高清| 麻豆av在线久日| 日日爽夜夜爽网站| 成年动漫av网址| 成人手机av| 黄色a级毛片大全视频| 99久久人妻综合| 一级,二级,三级黄色视频| 国产av国产精品国产| 欧美 日韩 精品 国产| 亚洲,欧美精品.| 日本vs欧美在线观看视频| 亚洲av片天天在线观看| 国产深夜福利视频在线观看| 国产精品 国内视频| 在线观看免费高清a一片| 在线亚洲精品国产二区图片欧美| 免费高清在线观看日韩| av网站在线播放免费| 久久久精品区二区三区| 99国产精品免费福利视频| 只有这里有精品99| 精品第一国产精品| 亚洲欧美一区二区三区国产| 日韩 欧美 亚洲 中文字幕| 国产精品一区二区在线观看99| 亚洲 国产 在线| 老汉色av国产亚洲站长工具| 精品国产一区二区久久| 中文乱码字字幕精品一区二区三区| 考比视频在线观看| 久久精品久久久久久噜噜老黄| 男男h啪啪无遮挡| 亚洲欧美色中文字幕在线| 最近最新中文字幕大全免费视频 | 亚洲精品中文字幕在线视频| 香蕉丝袜av| 91精品伊人久久大香线蕉| 国产精品二区激情视频| 国产成人av激情在线播放| 精品人妻在线不人妻| 91麻豆av在线| 免费看av在线观看网站| 国产熟女欧美一区二区| 日韩大片免费观看网站| 亚洲欧美清纯卡通| 国产xxxxx性猛交| 久久九九热精品免费| 亚洲中文日韩欧美视频| 丝瓜视频免费看黄片| 天天操日日干夜夜撸| 成人影院久久| 另类精品久久| 国产精品一区二区在线观看99| 国产一区亚洲一区在线观看| 不卡av一区二区三区| 久久毛片免费看一区二区三区| 汤姆久久久久久久影院中文字幕| 精品少妇内射三级| 久久精品熟女亚洲av麻豆精品| 亚洲一区二区三区欧美精品| 又紧又爽又黄一区二区| 一二三四社区在线视频社区8| 80岁老熟妇乱子伦牲交| 国产日韩欧美在线精品| 日韩熟女老妇一区二区性免费视频| 国产激情久久老熟女| 一级黄片播放器| 夫妻性生交免费视频一级片| 十分钟在线观看高清视频www| 最近手机中文字幕大全| 国产精品国产av在线观看| 精品熟女少妇八av免费久了| 咕卡用的链子| 波多野结衣av一区二区av| 叶爱在线成人免费视频播放| 精品欧美一区二区三区在线| 老司机在亚洲福利影院| www.999成人在线观看| 一本色道久久久久久精品综合| 激情视频va一区二区三区| 汤姆久久久久久久影院中文字幕| 国产黄色视频一区二区在线观看| 美女大奶头黄色视频| 曰老女人黄片| 中国美女看黄片| 亚洲专区国产一区二区| 免费人妻精品一区二区三区视频| 在线观看www视频免费| 一区二区三区精品91| 亚洲精品成人av观看孕妇| 国产女主播在线喷水免费视频网站| 美国免费a级毛片| 国产av精品麻豆| 咕卡用的链子| 性色av乱码一区二区三区2| 精品久久久精品久久久| 亚洲欧美一区二区三区黑人| a 毛片基地| 老鸭窝网址在线观看| 曰老女人黄片| 国产黄色免费在线视频| 一区二区三区激情视频| 欧美人与性动交α欧美精品济南到| 欧美日韩黄片免| 成人黄色视频免费在线看| 热re99久久精品国产66热6| 免费人妻精品一区二区三区视频| 婷婷色av中文字幕| 亚洲熟女精品中文字幕| 成人国产一区最新在线观看 | 亚洲成人免费电影在线观看 | 伊人久久大香线蕉亚洲五| 久久久精品国产亚洲av高清涩受| 黄色 视频免费看| 别揉我奶头~嗯~啊~动态视频 | 亚洲久久久国产精品| 黄片播放在线免费| 国产一区二区激情短视频 | www.自偷自拍.com| 国产97色在线日韩免费| 美女中出高潮动态图| 国产亚洲午夜精品一区二区久久| 国产一卡二卡三卡精品| 国产精品 国内视频| 亚洲一区中文字幕在线| 亚洲激情五月婷婷啪啪| 免费看av在线观看网站| 亚洲欧美精品综合一区二区三区| 日韩大码丰满熟妇| 欧美成人精品欧美一级黄| 日本一区二区免费在线视频| 精品亚洲成a人片在线观看| 一本—道久久a久久精品蜜桃钙片| 精品亚洲成国产av| 中文精品一卡2卡3卡4更新| 成年动漫av网址| av一本久久久久| 尾随美女入室| 国产成人免费无遮挡视频| 午夜福利在线免费观看网站| 欧美国产精品va在线观看不卡| 天天操日日干夜夜撸| 少妇 在线观看| 在线观看免费日韩欧美大片| 女人被躁到高潮嗷嗷叫费观| 两人在一起打扑克的视频| 天天躁狠狠躁夜夜躁狠狠躁| 国产精品免费大片| 亚洲成人国产一区在线观看 | 波野结衣二区三区在线| 久久精品亚洲熟妇少妇任你| 天堂中文最新版在线下载| 曰老女人黄片| 成人手机av| 纯流量卡能插随身wifi吗| 国产一区二区在线观看av| 丝袜喷水一区| 丰满人妻熟妇乱又伦精品不卡| 1024香蕉在线观看| 日日摸夜夜添夜夜爱| 夫妻性生交免费视频一级片| 在线 av 中文字幕| 免费看十八禁软件| 中文字幕亚洲精品专区| 国产成人免费观看mmmm| 日韩欧美一区视频在线观看| 高潮久久久久久久久久久不卡| 老汉色av国产亚洲站长工具| 久久青草综合色| 夫妻性生交免费视频一级片| 亚洲精品日本国产第一区| 亚洲一区二区三区欧美精品| 欧美成人精品欧美一级黄| 久久久精品国产亚洲av高清涩受| 丝袜喷水一区| 久久久久精品国产欧美久久久 | 色94色欧美一区二区| 国产成人a∨麻豆精品| 91精品三级在线观看| 青青草视频在线视频观看| 女人高潮潮喷娇喘18禁视频| 欧美精品高潮呻吟av久久| 汤姆久久久久久久影院中文字幕| 中文字幕精品免费在线观看视频| 男女床上黄色一级片免费看| 中文字幕最新亚洲高清| 国产在线观看jvid| 国产成人91sexporn| 伊人久久大香线蕉亚洲五| 香蕉国产在线看| 妹子高潮喷水视频| 国产国语露脸激情在线看| 国产亚洲精品第一综合不卡| 欧美中文综合在线视频| 久久久久精品人妻al黑| 亚洲精品国产av成人精品| 亚洲黑人精品在线| 另类精品久久| 性少妇av在线| 少妇被粗大的猛进出69影院| 久久久久久久精品精品| 亚洲九九香蕉| 久久人人爽人人片av| 免费在线观看黄色视频的| av在线老鸭窝| 欧美大码av| 成人免费观看视频高清| 亚洲国产精品成人久久小说| 麻豆国产av国片精品| 国产野战对白在线观看| 伦理电影免费视频| av有码第一页| 亚洲午夜精品一区,二区,三区| 久久免费观看电影| 18禁观看日本| 国产精品免费大片| 啦啦啦 在线观看视频| 热re99久久国产66热| 亚洲七黄色美女视频| 日韩中文字幕欧美一区二区 | 黄色 视频免费看| 久久久久久亚洲精品国产蜜桃av| 热99久久久久精品小说推荐| 国产成人a∨麻豆精品| 高清黄色对白视频在线免费看| 国产亚洲av高清不卡| 国产成人av教育| 日韩电影二区| av国产精品久久久久影院| 欧美激情高清一区二区三区| 亚洲成人免费电影在线观看 | 久久精品熟女亚洲av麻豆精品| 久久综合国产亚洲精品| 成人亚洲欧美一区二区av| 狂野欧美激情性bbbbbb| 午夜老司机福利片| 80岁老熟妇乱子伦牲交| 中文字幕高清在线视频| 欧美精品人与动牲交sv欧美| 天天躁夜夜躁狠狠躁躁| 午夜久久久在线观看| 看免费成人av毛片| 欧美国产精品va在线观看不卡| 一区二区三区精品91| 女人高潮潮喷娇喘18禁视频| 国产精品一区二区在线不卡| 五月开心婷婷网| 亚洲欧美中文字幕日韩二区| 日本午夜av视频| 国产日韩欧美在线精品| 一级毛片女人18水好多 | 亚洲欧美激情在线| av片东京热男人的天堂| 欧美激情 高清一区二区三区| netflix在线观看网站| 日韩av在线免费看完整版不卡| 激情视频va一区二区三区| 亚洲免费av在线视频| 欧美激情 高清一区二区三区| 精品国产国语对白av| 婷婷色麻豆天堂久久| 亚洲精品一区蜜桃| 中国国产av一级| 久久中文字幕一级| 亚洲精品在线美女| av又黄又爽大尺度在线免费看| 黄片小视频在线播放| 一本久久精品| 成年人黄色毛片网站| 在线观看一区二区三区激情| 亚洲欧美日韩高清在线视频 | 91精品三级在线观看| 热99国产精品久久久久久7| 中文欧美无线码| 欧美精品高潮呻吟av久久| 色视频在线一区二区三区| 亚洲欧美一区二区三区黑人| 少妇粗大呻吟视频| 国产成人啪精品午夜网站| 久久精品人人爽人人爽视色| 一级a爱视频在线免费观看| 亚洲欧美成人综合另类久久久| 成年动漫av网址| 男男h啪啪无遮挡| 亚洲一区二区三区欧美精品| 精品亚洲成a人片在线观看| 精品第一国产精品| 亚洲欧美一区二区三区黑人| 中文字幕亚洲精品专区| 一级毛片电影观看| 天天添夜夜摸| 久久久久久免费高清国产稀缺| 欧美黄色淫秽网站| 欧美黑人欧美精品刺激| 成年人午夜在线观看视频| 又大又黄又爽视频免费| 国产又色又爽无遮挡免| 亚洲欧美清纯卡通| 麻豆国产av国片精品| 亚洲精品久久成人aⅴ小说| 精品高清国产在线一区| 十八禁人妻一区二区| 无遮挡黄片免费观看| 免费在线观看日本一区| 久久久久久久久久久久大奶| av天堂在线播放| 天堂8中文在线网| 国产女主播在线喷水免费视频网站| 亚洲专区中文字幕在线| 国产精品一区二区在线不卡| 天堂中文最新版在线下载| 中文字幕制服av| 久久久精品94久久精品| 国产三级黄色录像| 美国免费a级毛片| av网站免费在线观看视频| 亚洲成人免费电影在线观看 | 亚洲 国产 在线| 日韩大片免费观看网站| 国产又爽黄色视频| 免费久久久久久久精品成人欧美视频| 国产主播在线观看一区二区 | 80岁老熟妇乱子伦牲交| 国产日韩一区二区三区精品不卡| 国产一区二区三区综合在线观看| 91精品伊人久久大香线蕉| 日本a在线网址| 亚洲欧美日韩另类电影网站| 如日韩欧美国产精品一区二区三区| www.自偷自拍.com| 欧美久久黑人一区二区| 人成视频在线观看免费观看| 日本五十路高清| 久久青草综合色| 中国美女看黄片| 国产成人系列免费观看| 日日夜夜操网爽| 国产精品国产三级专区第一集| 国产一区有黄有色的免费视频| 久久国产亚洲av麻豆专区| 免费人妻精品一区二区三区视频|