A:

Technically, a representative sample requires only whatever percentage of the statistical population is necessary to replicate as closely as possible the quality or characteristic being studied or analyzed. For example, in a population of 1,000 that is made up of 600 men and 400 women used in an analysis of buying trends by gender, a representative sample can consist of a mere five members, three men and two women, or 0.5 percent of the population. However, while this sample is nominally representative of the larger population, it is likely to result in a high degree of sampling error or bias when making inferences regarding the larger population because it is so small.

Sampling bias is an unavoidable consequence of employing samples to analyze a larger group. Obtaining data from them is a process that is limited and incomplete by its very nature. But because it is so often necessary given the limited availability of resources, economic analysts employ methods that can reduce sampling bias to statistically negligible levels. While representative sampling is one of the most effective methods used to reduce bias, it is often not enough to do so sufficiently its own.

One strategy used in combination with representative sampling is making sure that the sample is big enough to optimally reduce error. And while, in general, the larger the subgroup, the more likely that error is reduced, at a certain point, the reduction becomes so minimal that it does not justify the additional expense necessary to make the sample larger.

Just as the use of a technically representative but tiny sample is not enough to reduce sampling bias on its own, simply choosing a large group without taking representation into account may lead to even more flawed results than using the small representative sample. Returning to the example above, a group of 600 males is statistically useless on its own when analyzing gender differences in buying trends.

RELATED FAQS
1. ### What's the difference between a representative sample and a random sample?

Explore the differences between representative samples and random samples, and discover how they are often used in tandem ... Read Answer >>
2. ### How do systematic sampling and cluster sampling differ?

Systematic sampling and cluster sampling differ in how they pull sample points from the population included in the sample. Read Answer >>
3. ### What are the disadvantages of using a simple random sample to approximate a larger ...

Learn here what a simple random sample is, how researchers use it as a statistical tool and the disadvantages it carries ... Read Answer >>
4. ### What assumptions are made when conducting a t-test?

Learn what a t-test is and discover the five standard assumptions made regarding the validity of sampling and data used in ... Read Answer >>
5. ### What are some limitations of the consumer price index (CPI)?

Despite being followed so relentlessly, the consumer price index has its limitations and is an imperfect a measure of inflation ... Read Answer >>
Related Articles
1. Investing

### How to Use Stratified Random Sampling

Stratified random sampling is a technique best used with a sample population easily broken into distinct subgroups. Samples are then taken from each subgroup based on the ratio of the subgroupâ€™s ...
2. Personal Finance

### Birch Box Review: Is It Worth It?

Learn more about the subscription beauty box industry, and discover why the Birchbox company, in particular, has become so popular.
3. Investing

### Using Historical Volatility To Gauge Future Risk

Use these calculations to uncover the risk involved in your investments.
4. Investing

### How Vanguard Index Funds Work

Index funds allow investors to gain exposure to the market in a single, simple and easy-to-trade investment vehicle.
5. Investing

Human beings often act irrationally when it comes to business decisions. Behavioral finance explains the difference between what we should do and what we do.
6. Investing

### 4 Investing Biases You Should Avoid

Don't let these four behavioral biases interfere with your investment strategy and financial success.
7. Personal Finance

### Common Interview Questions for Accountants

Learn which job interview questions to prepare for to help advance your accounting career. Discover that what you do not say is as important as what you do say.
8. Investing

### Why Women Are Better Investors Than Men

Research shows that women are better investors than men.
9. Investing

### 4 Biases That Can Make You A Bad Investor

Find out how to spot these four biases, and start making more logical investing decisions.
10. Personal Finance

### How Women Uniquely View Finance and Investing

Understanding gender differences on financial-related issues and how they are changing over time is fundamental to understanding the investing world.
RELATED TERMS
1. ### Sampling Error

A sampling error is a statistical error that occurs when an analyst ...
2. ### Sample Selection Bias

Sample selection bias is a type of bias caused by using non-random ...
3. ### Stratified Random Sampling

Stratified random sampling is a method of sampling that involves ...
4. ### Acceptance Sampling

Acceptance sampling is a statistical measure used in quality ...
5. ### Law Of Large Numbers

The law of large numbers, in probability and statistics, states ...
6. ### Z-Test

A z-test is a statistical test used to determine whether two ...