The substitution bias in the customer price index refers to the:
1. Substitution by consumers toward new goods and away from old goods.
2. Substitution of new prices for old prices in the CPI basket of goods and services from one year to the next.
3. Substitution by consumers toward goods that have become relatively less expensive and away from goods that have become relatively more expensive.
4. Substitution by consumers toward a smaller number of high-quality goods and away from a larger number of low-quality goods.