By the end of 2017, there were 240.9 million elderly people aged 60 and over, accounting for 17.3 percent of the total population, and it is expected to reach 34.9 percent in 2050, when one in three people will be elderly, according to the 2017 Statistical Communique on the Development of Social Services . As a special group in urban life, with the increase of age, the physical function of the elderly begins to age, accompanied by psychological loneliness, loss and other negative emotions. Some data show that mental loneliness, mental illness and lack of spirit are the three major mental pension problems that often occur in the elderly . The degree of leisure activity participation is one of the important factors to determine the life satisfaction of the elderly. As the most widely distributed and closely related type of green space in urban green space, urban park green space provides the general public with the characteristics of easy to go, easy to form communication and gathering activity space, and plays an important role in strengthening the social communication among the elderly  . With the promotion of the concept of livable city, the word “adaptive transformation” has gradually become a hot spot. Bernard E, a British professor of geriatrics, once said: “if you design only for young people, you will exclude the elderly; if you design for the elderly, then consider the young people.” In this regard, it seems that any form of construction activities needs to include the needs of the elderly.
In the previous literature, the adaptability of urban parks to the aging of urban parks was discussed from the behavioral characteristics of the elderly   , such as Weiyi Yu, etc. . The evaluation system of elderly-oriented grassy area was constructed from the needs of the elderly for urban green space, which could be used as a reference for the transformation of urban parks. Yi Qu, Qing Lou, Zuoming Jiang, etc.     regard the activities of the elderly in the park, the degree of the elderly’s participation and the dependence of all kinds of activities on the venue as the basis for the optimization of park space and the improvement of utilization rate. Huan Wang etc.  focus on the current situation of park public space and the special activities of the elderly. Combined with the information provided by the management department, this paper makes a comprehensive evaluation of the park, and some scholars start with the differentiated personal attributes of the elderly and study the elderly-oriented level of the parks by studying the needs of the low-income elderly and the intensity of the use of the park by the elderly of different ages  . The studies above provide theoretical basis and guidance for the aging transformation of parks from different angles. But there is a lack of study of the elderly-oriented level of parks which is mainly determined by the subjective satisfaction of the elderly. Other scholars focus on the fitness function of urban parks, and propose that parks can not only meet the physical and psychological needs as well as the multi-level and multi-type needs of the elderly, but also combine the time and space convenience with their individual talents and interest, which will enable them to form their own ecological chains featuring by leisured sports .
2. Research Method
Data Source Analysis
The content of the questionnaire was composed of three parts: personal attribute, satisfaction evaluation and attention ranking of the elderly. In December 2018, a questionnaire survey and field interview were conducted among the elderly who were active in Mianzhu people’s park. A total of 200 questionnaires were sent out and 186 valid questionnaires were collected. in order to increase the understanding of the elderly and better sort out the results of data analysis, 20 elderly people were randomly selected for in-depth interviews in the course of the survey. SPSS statistical analysis software is used to describe the survey data and regression analysis.
The results of the survey are shown in Table 1. From the point of view of physical condition, the poor health and physical condition of the elderly account for a small proportion, most of the elderly belong to the good category, so the layout of the facilities in the park should be able to meet the needs of the elderly group with poor health. From the point of view of the purpose, 51.6% of the elderly come to exercise. Some studies have shown that health demand is a common psychological state of the elderly. Due to the varying degrees of limitations caused by their own weakness, most of the elderly will choose a healthy lifestyle . Therefore, most of the elderly have higher requirements for physical fitness facilities, and 30.1% of the elderly are in order to participate in social activities, they may be more demanding on public communication space, the rest of the elderly are to play with children or for other purposes, so they may not be very targeted to a specific element, and their activities are more flexible and extensive.
3. Satisfaction Evaluation
3.1. Construction of Evaluation Factor Set
In the past study, the index selection method is different, such as Yuequn Liu,
Table 1. Personal attributes of the elderly.
Zhen Zeng, Chunwei Zhang et al.   . After reading the relevant literature at home and abroad, the index system used in the study was summarized. And then the evaluation factors are refined according to the research content of the invention. In the comprehensive evaluation of the park, the reference system for other scholars should be used for reference, and the evaluation system should be revised by reference to the suggestions given by the professionals, and the factor analysis method will be used finally. The evaluation factor set is determined by the statistical methods such as the analytic hierarchy process  .
The selection of evaluation indexes in this study is based on the four element levels of “safety”, “health”, “convenience” and “comfort”  mentioned in the book “Residential Environment: evaluation methods and theories”. Next, the four standard layer elements are refined according to the opinions of professionals and park managers. Finally, 10 evaluation factors were selected to measure the satisfaction of the elderly with the people’s park, and the evaluation factor set U = [number of toilets, landscape effect, barrier-free transportation, street lighting, physical fitness facilities, entertainment facilities, noise interference, environmental hygiene, public communication space, richness of recreational activities].
3.2. Single Factor Satisfaction Analysis
In order to avoid the distortion of the results caused by a single either or other evaluation, this study selected the Likert scale to divide the satisfaction of the elderly into five dimensions: “very satisfied, general, dissatisfied, very dissatisfied” and assigned it a score of 5 to 1, which constitutes the evaluation set V, V = [5, 4, 3, 2, 1], and the evaluation index belongs to the ratio of the number of people who belong to the comment set V to the total number of people participating in the questionnaire. The membership matrix of each evaluation factor can be obtained. If the elderly are very satisfied with the frequency of satisfaction with the number of toilets, 28 are satisfied, 92 are general, 46 are dissatisfied and 12 are very dissatisfied. The membership matrix V1 = [0.043, 0.151, 0.494, 0.247, 0.065], and the satisfaction membership matrix of other factors can be obtained, and the fuzzy relation matrix of satisfaction can be obtained by combining V1-V10 vector with the fuzzy relation matrix of satisfaction.
According to R, the highest satisfaction rate was environmental hygiene, 44.1% of the elderly gave a positive evaluation of it, and only 17.2% of the elderly gave a negative evaluation. On the contrary, street lighting was the lowest satisfaction, 61.3% of the elderly gave negative evaluation, only 5.4% of the elderly made a positive evaluation, Entertainment facilities, richness of recreational activities and public communication space are followed successively. More than 50% of the elderly give negative evaluation to these three factors. In the satisfaction evaluation of the number of toilets and noise interference, the elderly with neutral attitude are in the majority, with 49.4% and 48.4% respectively rating them as average.
Therefore, the evaluation of various factors by the elderly is different, and the evaluation of individual factors is higher, while most factors are lower, so it can be inferred that the satisfaction evaluation of the elderly to the park is not high.
3.3. Analysis of Overall Satisfaction
In the questionnaire survey, the elderly were asked to select 3 important factors out of 10 evaluation factors and rank them. In this study, the comparative sorting method was used to determine the weight of each factor. The assignment principle was 3 points for the first important factor, 2 points for the second important factor, and 1 for the third important factor. The formulas are as follows:
In the formula, “Wj” is the weight coefficient of the evaluation factor “j”, “n” is the total number of evaluators (n = 186); “kij” represents the score obtained by ranking the evaluation factor “j” by the evaluator “i”, “m” is the number of evaluation factors (m = 10).
The comprehensive weight, W = [0.089, 0.097, 0.075, 0.070, 0.131, 0.125, 0.098, 0.140, 0.107, 0.0.068], i.e. the most important environmental hygiene is widely considered in the elderly, followed by the physical fitness facilities and entertainment facilities; However, the importance of street lighting, barrier-free transportation and the richness of recreational activities are relatively low in the elderly.
The comprehensive weight W of 10 evaluation factors and the fuzzy relation matrix R can be combined with matrix multiplication to obtain the fuzzy comprehensive evaluation result E of the elderly’s satisfaction with the park. That is, E = R × W = [0.033, 0.113, 0.391, 0.106]. The above results show that the maximum membership degree of “general” in the fuzzy comprehensive evaluation of park satisfaction is 0.391. on behalf of 39.1% of the elderly, 39.1% of the elderly maintain a neutral attitude towards the evaluation of park satisfaction, 3.3% and 11.3% of the elderly are “very satisfied” or “satisfied”, respectively, that is, only 14.6% of the elderly make a positive evaluation, while the remaining 42.1% of the elderly give a negative evaluation. It can be seen that the overall satisfaction of the elderly with the park is not high, which is consistent with the inference results after the above-mentioned 3.2 Single Factor Satisfaction Analysis, and the degree of attention of the elderly to the 10 evaluation factors is different, The distribution characteristics of each factor under the double evaluation of satisfaction and importance ranking will be analyzed in the following.
3.4. Classification and Analysis of Satisfaction and Concern
By multiplying the number of people who choose “very satisfied” to “very dissatisfied” with the assignment corresponding to the evaluation, the scores of each of the five evaluation levels can be obtained, and then the scores of the same factor on the five evaluation levels can be added together, thus the comprehensive satisfaction scores of 10 factors can be obtained. In addition, the X-axis is divided into the factor comprehensive satisfaction score, and the weight is divided into the Y axis to produce the scatter chart as shown in Figure 1. The surface is divided into four parts: “high satisfaction-high attention”, high-satisfaction-low-attention”, “low satisfaction-low attention” and “low-satisfaction-high attention”.
For the “high satisfaction-high attention” and “high-satisfaction-low-attention”, those factors in these two categories are the guarantee of high satisfaction for the elderly, so we should make rational use of the advantages of these two categories in the daily management and transformation of the park. For the “low satisfaction-low attention”, if the elderly pay less attention to this kind of factors, the requirements will not be too high, but the park as a municipal public service facility should at least ensure the normal activities of the elderly. For the “low satisfaction-high attention”, this kind of factors is the key to improve the overall satisfaction of the elderly and the root cause of the low overall satisfaction of the elderly. Therefore, in order to improve the overall satisfaction, special attention should be paid to the public communication space, entertainment facilities, physical fitness facilities and other factors of repair and improvement. The evaluation factors of 7/10 fall in the “low satisfaction” quadrant, which proves the fact that the elderly are not satisfied with the park more intuitively, and also means that the improvement of this kind of factors will be beneficial to improve the satisfaction evaluation of the elderly.
3.5. Analysis of Single Factor Influencing Factors
In order to explore the specific reasons that affect the satisfaction evaluation of each factor, this paper analyzes the correlation between the personal attribute variables of the elderly and the satisfaction evaluation results of each factor in Table 1, and finds that the personal attributes of the elderly are generally related to the evaluation of each factor: 1) Age are related to the number of toilets, landscape effect, street lighting; 2) Educational level, physical condition and the satisfaction of amusement richness are related; 3) There is a correlation between living status and the satisfaction of entertainment facilities; 4) The satisfaction of physical fitness facilities and street lighting are highly related to the travel purpose; 5) The physical condition and the satisfaction of the number of toilets are also correlated (Table 2).
3.6. Analysis of Comprehensive Influencing Factors
In the above analysis, only the pairwise correlation between the personal attributes of the elderly and the variables in the satisfaction evaluation of each factor is verified, and the influence of the interaction between the multiple personal attributes on the satisfaction evaluation of the elderly are not taken into account. Therefore, the following regression analysis is carried out by using the satisfaction evaluation of each factor as dependent variables and the personal attributes of the elderly as independent variables. It is found that the following three factors affect the evaluation of the satisfaction of the elderly with each factor:
Figure 1. Satisfaction-attention dispersion map for the elderly.
Table 2. Correlation analysis of individual attributes and evaluation factors.
1) From the point of view of age and physical condition, with the increase of the age of the elderly, the satisfaction with the number of toilets, landscape effect, barrier-free transportation, street lighting and public communication space will show a downward trend. The worse the physical condition of the elderly, the more dissatisfied with the number of public toilets and barrier-free traffic factors. Due to the increase of age, the physical functions and mobility of the elderly are gradually degraded, the frequency of going to the toilet is frequent, the visual acuity is declining and so on. Therefore, they are more inclined to choose sit-in, viewing and other activities with less intensity, as well as relatively safe and convenient spatial factors, which is manifested in their dependence on the corresponding facilities. The degree of dependence has increased significantly.
2) From the point of view of the purpose of physical exercise, compared with the elderly with children, the satisfaction of the elderly with physical fitness facilities decreased by 0.520 units, and the elderly with the purpose of exercising naturally paid more attention to physical fitness facilities. 51.6% of the elderly in this study took exercise as the purpose of travel. The lack of quantity and quality of physical fitness facilities in the park is the main reason for its low satisfaction. Therefore, park managers should consider adding relevant facilities and carrying out quality maintenance regularly in order to meet the needs of elderly users and improve satisfaction.
3) Compared with the elderly with walking time of less than 15 minutes, the satisfaction of the elderly with walking time of more than 30 minutes with the number of toilets decreased by 0.246 units from the point of view of living distance. According to Sina.com, the human body generally needs 30 minutes from water intake to discharge, so it seems that the time required for human water metabolism coincides with more than 30 minutes of walking time, while the decline in the physical control ability of the elderly leads to the low satisfaction of elderly tourists living far away from the number of toilets. So it seems that consideration can be given to properly increasing the number of toilets in crowded areas at the entrance and exit of the park.
In order to explore the relationship between the personal attribute of the elderly and the evaluation of the overall satisfaction of the park, the following paper uses the evaluation of the overall satisfaction of the elderly as dependent variables and individual attributes as independent variables to carry out multiple linear regression analysis, and the linear regression equation can be obtained. , That is to say, the younger the age (x1), the higher the education level (x2), the higher the evaluation of the overall satisfaction of the park. The specific performance is that when the education level remains the same, compared with the 60 to 69 years old, the elderly will be 10 years longer each year, and their satisfaction will be reduced by 0.383 units. When the age of the elderly remains the same, compared with the elderly with primary school and below, their satisfaction will be increased by 0.277 units for each grade of educational background. In general, the elderly, who are young and highly educated, have a wide range of interests and hobbies, and the participation of various activities is more likely to be integrated. In order to improve the overall satisfaction of the elderly, we should pay more attention to the needs of the elderly with high age and low educational level.
In this paper, through the fuzzy evaluation of the satisfaction of the elderly, it is found that the overall satisfaction of the elderly to the park is generally low, mainly concentrated on the “general” and “unsatisfactory” level. These remarks are specified to every factor of the parks. The elderly have demonstrated high satisfaction and close attention to the environmental sanitation. They have also shown high satisfaction and low attention to noise interference and the number of toilets. Likewise, physical fitness facilities, entertainment facilities and public communication area attract high attention and get low satisfaction. Moreover, the elderly all show low satisfaction and low attention to street lamps, barrier-free transportations, landscape effect, and the richness of recreational activities. In view of the impact of the individual attributes of the elderly on the satisfaction evaluation, the results of the satisfaction evaluation and the personal attributes were analyzed. The results show that the results of satisfaction evaluation and personal attributes are analyzed by regression analysis. The younger and better educated the elderly are, the more satisfied they are with the park. The less active the elderly are, the less satisfied they are with such factors as the number of toilets, landscape effect, barrier-free transportation, street lighting and public communication space. Due to the enhancement of health care consciousness, the number of sports and fitness facilities in the park cannot meet the daily use needs of the elderly. The number of toilets should be increased, and should be arranged in the park entrance and other areas where people gather.
It is learned from the interview that most of the elderly suffer from chronic diseases such as hypertension and diabetes, and want to maintain their physical condition through active exercise. Therefore, in the later management and renewal of the park, we should consider the special needs of the elderly group, add physical fitness facilities and recreational facilities, and let more elderly people participate in it. At the same time, more organizations carry out health lectures, Taiji and other recreational activities to arouse the enthusiasm of the elderly. In terms of landscape effect, we can enrich the landscape of the park through plant collocation, ensuring that spring flowers can be enjoyed, summer shade can be taken, autumn and winter colors. Meanwhile, the lighting facilities should be repaired in time, adding street lamps and seats in remote and leafy areas.
Supported by Science & Technology Department of Sichuan Province (Grant No. 2019JDR0119). Innovation Fund for Graduate Students of Southwest University of Science and Technology (Grant No. 19YCX0082).
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