## 3 Survey Design  
This research is based on a collection of individual data, such as the answers from TSE investors to a particular set of questions. The questions surveyed their attitudes towards specific cognitive fallacies in the context of financial investment. Some crucial aspects of the survey design are discussed below. Firstly, in addition to a good sample, an effective survey design requires the **robust design of questions** that can reliably reflect people's thoughts, experiences, and public actions. Accurate random samples and high response rates may not be possible if the information obtained is subject to uncertainty or bias. The fundamental development of suitable measures includes writing suitable questions and then arranging them in a questionnaire format. The questionnaire constitutes a multi-stage process that highlights and scrutinizes many details simultaneously. The task of designing the questionnaire is not a straightforward one, since questions can be asked in various formats and to different levels of detail. Questions posed earlier in the survey can also affect how participants respond to later questions. The survey design process becomes more intricate when it involves the estimation and measuring of the degree of psychological biases. It is necessary for us to scrutinise all aspects of design, including verifying the order of questions, in order to ensure that the respondents answer each question accurately, which ultimately gives us the means for our study. All these aspects were considered when designing a questionnaire (see Appendix A) which addresses the cognitive fallacies discussed. Secondly, one should understand the **institutional environment** of interviewees. The research was conducted on the Iranian Stock Exchange. There are a wide variety of entities active in the Iranian capital market (Figure 1). There are four exchanges, comprising two equity markets, TSE (Tehran Stock Exchange) and IFB (Iran Fara Bourse), and two commodity markets, IME (Iran Mercantile Exchange) and IRENEX (Iran Energy Exchange). They are supported by institutions such as CSDI (Central Securities Depository of Iran), and IDS (Information Dissemination Services), and associations such as IIIA, SEBA, and TSETMC (Tehran Securities Exchange Technology Management Co.). Since November 2005, the Tehran market has been in its fourth stage of development, oriented towards attracting small investors and financing companies. As of September 2021, TSE's total market capitalisation was USD 1,427,595,000 (CEIC data). As these markets play a constructive role in the allocation of resources and national capital, they are heavily relied upon for the economic development of society. TSE has a similar structure to other markets of its size and impact, which increases the transferability of results. Figure 1: Iran’s capital market structure. Thirdly, the survey should mimic the **behavioural conditions** of decision-makers; this may lead to a high degree of consistency in the questionnaire and participants' natural reactions. The psychological aspect of decision-making in the stock markets cannot be overlooked, since many investors tend to bypass rationality and, at some point, rely solely on intuition. These effects, which can also be referred to as fallacies, are based on feelings, emotions, and intuition, rather than on rational considerations, and they often result in inferior financial performance [27]. Additionally, cognitive biases can be understood as \"hard wired\" actions [37], making us all liable to take shortcuts, oversimplify complex decisions and be overconfident in our decision-making processes. Therefore, understanding the cognitive fallacies of the stock market holders can lead to better decision being made, which is fundamental to lowering risk and improving investment returns over time.