Final answer:
The impact of a 10% increase in shelter costs on the CPI depends on shelter's weight within the CPI basket and cannot be determined precisely without that information. A numerical example would be a 3% increase in the CPI if shelter costs represent 30% of the basket. The CPI may also have biases and might not fully reflect online prices.
Step-by-step explanation:
The question involves understanding how changes in the cost of certain items affect the Consumer Price Index (CPI), which is a measure of the average change over time in the prices paid by urban consumers for a market basket of consumer goods and services. If the cost of shelter, which is a significant part of this basket, increases by 10 percent, the impact on the CPI will depend on the weight that shelter costs have within the total CPI basket. It is not typically the case that the CPI would increase by the same percentage as any single item within the basket, unless that item solely comprised the entire CPI, which is not the case.
To arrive at the precise impact on the CPI, we would need the weight of the cost of shelter in the CPI. For example, if shelter costs represent 30% of the CPI, a 10% increase in shelter costs would result in roughly a 3% increase in the CPI (0.10 * 0.30 = 0.03). However, without the specific weights, the exact percentage cannot be determined, and thus the question cannot be answered definitively. Actual percentages would vary based on the detailed composition of the CPI basket and the weight assigned to shelter within it.
It is also important to note that the CPI is subject to potential biases such as substitution bias and quality/new goods bias, and it may not fully reflect online pricing from sites like Amazon which can be lower.