This research aimed to study environmental and social disclosure levels the relationship between performance and environmental and social disclosures and the comparison of the performance and environmental and social disclosures of industrial product companies and the resource industry group listed on the Stock Exchange of Thailand. The secondary data was collected from financial statements annual reports and the data entry forms (Form 56-1) from 2015 to 2019 of the total of 130 companies. Descriptive statistics were used for the analysis namely mean and standard deviation. Inferential statistics such as correlation analysis and multiple regression analysis were also used. The research results showed that there was a Statistically significant correlation between the performance and the environmental and social disclosures of the companies in the industrial product group including reusing aspects environmental monitoring aspects and environmental law aspects and the return on equity (ROE) debt ratio (DR) and stakeholder equity (SE) at the levels of 0.01 and 0.05. In the resource industry group there was a statistically significant correlation between environmental and social disclosures namely recycling aspect with return on equity (ROE) debt ratio (DR) and income at the levels of 0.01 and 0.05.

This research aimed to study earning quality sustainability factors (ESG) and the relationship between earning quality and sustainability factors of the 59 companies listed in the sustainability index (SET THSI INDEX). The data was collected from the financial statements annual reports sustainability report and the data entry forms (Form 56-1) from 2015 to 2019. Descriptive statistics and inferential statistics were used in the data analysis including correlation analysis and multiple regression analysis The results of the study showed that most of the companies listed in the SET THSI Index had higher earning quality than the index average. The sustainability factor that has the greatest influence on earning quality is good governance. When the relationship between earning quality and sustainability factors (ESG) was analyzed it was found that there was a statistically significant correlation between environmental disclosures and good governance namely the number of the Board of Directors shareholding by Thai juristic person at the levels 0.01 and 0.05. There was a statistically significant opposite correlation between the disclosure of social responsibility information including anti-corruption aspect human rights aspect and responsibility to consumer aspect; and good governance including the proportion of shares held by family companies at levels 0.01 and 0.05.

The research objective is to study the relationship between environmental disclosure levels corporate governance and the performance of companies listed in the Real Estate and Construction group on the Stock Exchange of Thailand. It was conducted by collecting information from the financial statements the annual reports and the information registration forms (Form 56-1) of 91 companies from 2015 to 2019. Descriptive statistics and inferential statistics were used in data analysis including correlation analysis and multiple regression analysis. The study results showed that environmental disclosure levels including environmental policy disclosure and other environmental disclosures positively correlate with the rate of return on equity return on total assets with a statistical significance at 0.01 and 0.05 levels. Corporate governance including the percentage of shareholding by the management and the number of the Board of Directors positively correlates with the return on total assets with a statistical significance at 0.01 and 0.05 levels.

This research aimed to study the relationship between financial ratios of operating efficiency and profitability of listed companies on the Stock Exchange of Thailand. Data was collected from the financial statements of the real estate and construction groups from 2015 to 2019. The data were analyzed using descriptive statistics such as frequency percentage mean and standard deviation. The inferential statistics were Pearsons Correlation Coefficient and Multiple Regression Analysis. The results of the study found that 1. operating cash flow activities positively correlated with the return on asset 2. the debt to asset ratio was negatively correlated with the gross profit margin net profit margin return on asset and return on equity 3. average collection period was negatively correlated with the gross profit margin and net profit margin 4. inventory turnover had a negative correlation with the return on asset 5. the total asset turnover was positively correlated with the net profit margin return on asset and return on equity with the statistical significance at a level of 0.05.

The objective of this research was to study the investors’ investment volumes affecting the Price change of the ETF SET 50 mutual fund in the Stock Exchange of Thailand. This research was the Quantitative Research. The descriptive statistics was used to test the preliminary data and used the Multiple Regression Analysis of the Inferential statistics to test the hypothesis and used Pearson Correlation to find the relationship between independent variables by using the daily data of the past five years start from January 1 2012 to December 31 2016. The results of the study found that the investment volumes of domestic institutional investors’ portfolio account of foreign companies and general investors affected the Price change of the ETF SET 50 mutual fund and the SET 50 stock price index in the Stock Exchange of Thailand at the 0.05 significant levels. The SET 50 stock price index was highly and positively related to ETF SET 50 mutual fund price change in the Stock Exchange of Thailand at the 0.01 level of statistical significance