Operational Efficiency

The word "efficiency" gets used two different ways in markets, and the workbook is careful to separate them before going further. Operational efficiency is about cost — how much it costs to actually buy or sell. Informational efficiency is about price — whether that price already reflects everything knowable. They are related but genuinely different questions, and a market can score well on one while scoring poorly on the other.

The workbook opens the chapter with the distinction: "Operational efficiency measures the cost of transacting i.e. cost of carrying out trades in the market. Thus, it is concerned with transactions costs. Market is said to become operationally efficient if the cost of transacting in the market is going down... Popularly the term market efficiency is used in the context of informational efficiency rather than operational efficiency."

Illustrative figures, not from the workbook. If the round-trip cost of trading a large-cap NSE stock — brokerage, statutory charges and market impact combined — falls from roughly 40 basis points a decade ago to roughly 15 basis points today, that decline is a rise in operational efficiency. It says nothing, by itself, about whether today's price is a better estimate of fair value than the price a decade ago — that second question is informational efficiency, and the workbook explicitly separates the two so students do not treat a falling transaction cost as proof of a more informationally efficient price.

Over the 2000s and 2010s, Indian equity trading costs fell sharply as dematerialisation, electronic order-matching and discount broking reduced brokerage and settlement costs — a clear improvement in operational efficiency. NSE's shift to fully electronic, screen-based trading and shorter settlement cycles is the kind of development the workbook's definition points to.

That cost reduction did not, on its own, make Indian markets more informationally efficient. A stock can still be mispriced relative to its fundamentals even when it is cheap and fast to trade — the two properties are independent. A portfolio manager exploiting a genuine informational edge benefits directly from lower operational costs (more of the edge survives after costs), but low costs do not create the edge in the first place.

Chapter 13, section 13.1 (Informational Efficiency versus Operational Efficiency), opens the chapter with exactly this contrast before moving on to the EMH and its three forms. Expect a definitional question distinguishing the two kinds of efficiency, often as the first question in the chapter's set.

• "Market efficiency" in everyday use almost always means informational efficiency — the workbook flags this explicitly as the common usage, which makes operational efficiency the easy-to-miss distractor in a definitional question.
• A falling transaction cost proves operational efficiency, not informational efficiency. Do not treat the two as the same evidence.
• Operational efficiency is a cost concept; informational efficiency is a price accuracy concept — keep the nouns straight when answering.