Home bias
Also written Home (familiarity) bias · Familiarity bias
Investors' tendency to hold far more of their own country's securities than its share of world markets justifies, because the familiar feels less risky.
In plain language
If investors simply held the world market, each country would get roughly its share of global market capitalisation. They do not. Almost everywhere, investors hold much more of their home market than that.
The workbook calls this home bias, or familiarity bias. Investors know the domestic companies, products, laws, taxes and consumer behaviour — and that familiarity makes local investments feel less risky than they are.
The cost is not that home markets are bad. It is that the portfolio becomes concentrated in one economy, and gives up the diversification that other markets, moving on different cycles, would provide.
How it works
The workbook's evidence (Chapter 18, section 18.14.4). The US represents 54% of world market capitalisation, yet the average US investor holds approximately 80% in US markets. A Vanguard report published in 2017 shows the same pattern elsewhere:
| Country | Global index weight | Investors' holding in domestic market |
|---|---|---|
| USA | 50.9% | 79.1% |
| Canada | 3.4% | 59.0% |
| UK | 7.2% | 26.3% |
| Australia | 2.4% | 66.5% |
| Japan | 7.2% | 55.2% |
The Indian market is merely 2% of the global market, yet the average Indian investor's overseas exposure is negligible. The workbook says regulation was one reason, but familiarity and bias towards local companies is the main one — and that this is changing with ETFs and with the government allowing USD 2,50,000 a year for overseas investment.
Reasons for home bias: familiarity, optimism about the local economy, perceived risks of investing overseas (currency, geopolitics), and predictability that is high or perceived to be high.
Two major disadvantages: concentration of the portfolio, and missing out on diversification opportunities.
A worked example
Illustrative figures. Dr. Farah Khan, a Pune surgeon, has ₹3 crore in financial assets — every rupee in Indian equities, Indian debt and Indian real estate funds. Her reasoning: "I know these companies. I have no idea what is happening in Korea or Germany."
India is about 2% of the global market. A market-weight investor would hold roughly ₹6 lakh of ₹3 crore in India. Nobody sensible suggests that — Indian liabilities, currency and goals justify a strong domestic tilt. But 100% means her portfolio is fully exposed to a single economy's cycle, policy decisions and currency.
Her portfolio manager proposes moving 20% — ₹60 lakh — into global equity over two years, through feeder funds and ETFs and, for direct holdings, within the Liberalised Remittance Scheme limit of USD 2,50,000 per financial year. At an assumed rate of ₹85 to the dollar, that limit is about ₹2.1 crore a year, so the ₹60 lakh fits comfortably.
The workbook's Chapter 18 table sets out what she takes on in exchange: benefits of diversifying country-specific risk, superior risk-adjusted return and tactical opportunities; costs of liquidity risk, geopolitical risk, currency risk, higher regulatory cost for direct investment, and delays in information.
Why NISM asks about it
Chapter 14 (Behavioural Finance), section 14.1, lists preferring domestic companies because familiarity makes the risk seem low as one of the ways real investors differ from standard finance theory. Chapter 18 (Equity Portfolio Management Strategies), section 18.14.4, treats home (familiarity) bias in detail with the US and Vanguard figures, its four reasons and its two disadvantages, inside the discussion of global active strategy.
Common exam traps
- The workbook gives the US share three ways. Section 18.14.1 says US markets account for more than 50% of world market capitalisation; section 18.14.4 says 54%; its Vanguard table says 50.9%. Match the figure to the context the question uses.
- The two disadvantages are concentration and missed diversification — not higher costs or lower liquidity (those are costs of going global).
- Four reasons: familiarity, optimism, risks (currency, geopolitical) and predictability.
- India is about 2% of the global market in the workbook, with negligible overseas exposure by Indian investors.
- The overseas allowance is USD 2,50,000 a year (the LRS limit, which Chapter 9 describes as per financial year for resident individuals, including minors).
- Home bias is a behavioural bias; a deliberate domestic tilt to match rupee liabilities is a reasoned allocation choice. The bias is the gap between the two.
Where this is taught
- Series XXI-B · Chapter 14: Behavioural Financeintroduced here
- Series X-B · Chapter 16: Basics of Behavioral Financeintroduced here
Related terms
- DiversificationSpreading an exposure across holdings that do not move together, so that total risk falls by more than total return does — minimising risk per unit of return.
- Overconfidence biasAn emotional bias in which people place unwarranted faith in their own judgement and abilities — leading to underestimated risk, concentrated portfolios and excessive trading.
- Strategic asset allocationThe long-term target split of a portfolio across asset categories, fixed from the investor's goals, time horizon and risk profile rather than from any view on markets.
- Mental accountingA cognitive error in which people treat equal sums of money differently depending on where they came from or what they are earmarked for, instead of treating all money as interchangeable.
- Illusion of controlThe belief that familiarity, information access or active involvement gives an investor influence over a price — which leads to a conviction that he can forecast it and sell out before everybody else.
- Availability heuristicThe habit of judging an investment by whichever example comes to mind fastest — a friend's tip, a headline, an advertisement — instead of by actually researching it.