That sounds like a very interesting MPhil topic! Here are some thoughts to get you started on your research on the vegetable marketing system in Dhaka city:

Research Focus

• Traditional vs Modern: You could analyze the interplay between the traditional system with Beparis and Aratdars and the emergence of modern supermarkets and cold chains.
• Efficiency and Price Fluctuations: How efficient is the current system? Does it lead to high price fluctuations for consumers?
• Farmer's Share: What share of the final price do farmers receive? Are there ways to increase their profits?
• Sustainability: Is the system sustainable considering factors like climate change and population growth?

Data Collection

• You will likely need data from multiple sources:
  • Interviews with farmers, Beparis, Aratdars, and retailers.
  • Data from government agencies on agricultural production and market prices.
  • Case studies of successful modern vegetable marketing initiatives.

Analysis Techniques

• Cost-benefit analysis to assess the efficiency of the current system.
• Econometric modeling to understand the factors affecting vegetable prices.
• Comparative analysis to compare Dhaka's system with other cities.

Here are some resources to get you started

• Existing Research: A good starting point is to find existing research on the topic. You can search for academic journals using databases like JSTOR or Google Scholar. Here are some keywords to use: "vegetable marketing system," "Dhaka," "Bangladesh," "farmers," "intermediaries," "efficiency," "price fluctuations."
• Government Agencies: The Bangladesh Department of Agriculture Marketing and the Ministry of Agriculture may have data relevant to your research.
• News Articles: Local and national news articles can provide insights into current issues and challenges faced by the vegetable marketing system.

MPhil Requirements

• Make sure you understand the specific requirements for your MPhil program at your university.
• Talk to your potential thesis supervisor to get their guidance on your research topic and methodology.

I hope this helps! Good luck with your MPhil research.