When businesses want to conduct research on their products or marketing, they often rely on gathering data from consumers and other people in the market. However, using data from every single person in a population could mean sorting through millions of opinions and pieces of information for some businesses, which is highly inefficient and costly. To combat this, researchers use sampling, which involves gathering and analyzing data from a group within the population. When done correctly, the results of the research conducted on the sample are representative of the whole population, but sometimes it can be inaccurate due to sample bias.
What is Sample Bias?
Sample bias is when your sample is not representative of the overall population. This is generally due to flaws in your sampling method. Let’s look at some of the most common types of sample bias:
Undercoverage Bias: This occurs when certain groups are underrepresented or excluded in the sample. For example, it would be an undercoverage bias if your business runs a survey and does not account for certain demographics.
Non-Response Bias: This occurs when people refuse to or are unable to respond to your survey, most frequently showing in voluntary surveys. As a result, your data will generally consist of more extreme opinions.
Observer Bias: This occurs when the surveyor unintentionally influences the respondents’ answers. For example, if you mention specific statistics that support your side before asking for a response, the responses will likely be skewed in your favor.
There are many other types of sample biases, but these three are very common in business research and should be avoided.
How can you avoid Sample Bias?
For your data to be as accurate as possible and lead to practical solutions, you will need to avoid sample bias. Listed below are some ways you can do so:
- Avoid convenience sampling. This is when the researcher collects data and generates the sample from the people who are easiest to reach. Often, convenience sampling results in a sample that is not proportionate to the actual population.
- Use proportional sampling. If a particular group of people makes up 40% of the population, they should compose around 40% of your sample. This leads to a sample that accurately represents the population.
- Do not oversample. To avoid sample bias, many researchers will gather more responses from certain “underrepresented” groups, causing those groups to make up a more significant part of the sample than the actual population. This is another form of sampling bias.
- Keep surveys short and simple. More people will reach the end and submit the survey if it is short, eliminating some non-response bias.
- Design your survey so that the responses are minimally affected by their surroundings and the surveyor. This will help reduce the amount of observer bias in your research, which can go completely unnoticed.
Following these tips and understanding the different types of sample bias will help you minimize the amount of bias in your research, making it as accurate as possible.