Determining Sample Size for Online Surveys

Earn Money with only an opinion!

How to determine sample size for online surveys varies hugely.

Factors on this decision include budget constraints, sample availability, time available, etc. Obviously a sample of 1000 individuals will produce more accurate survey results versus a sample of only 100 people. This is simply because generally, a larger group of people will more accurately reflect the attitudes of an even larger group, simply because there is more individual variety, and this therefore will yield a larger variance in answers.

Now, admittedly this is a general and over-simplified answer. Complicated statistics on sample sizes, confidence intervals, and statistical validity on how all of these relate would better explain how this all works.

A similar question was posted on Infosurv's website, and the following response was provided:

"To achieve statistically valid results, we recommend that a statistically significant sample of n=400 completed surveys be obtained for online market research surveys. This will provide statistical validity at the 95% confidence level with +/- 5% confidence interval. For clients on a tighter budget, we sometimes recommend a sample of n=200 completed surveys which provides statistical validity at the 95% confidence level with +/- 7% confidence interval. In any event, a reliable sample source is very important, as is an unbiased random sampling methodology."

"n" in this case simply represents the number of people comprising the sample.

As you can see then, there needs to be a decent sized sample in order to eliminate as much bias as possible. This does not mean that it is necessary to conduct a survey with 100,000 participants in order to get accurate answers.

What does this mean for you? When there is a chance to win cash or product as a survey participant, keep in mind that your chances of winning are decent. The chances of winning the jackpot in a national lottery are usually more than 1 in 10,000,000, and you must purchase a ticket, which involves a cost. You could very well be offered a chance to win a plasma tv worth $5000 for 15 minutes of your time, when there are only a few hundred other participants. What are you waiting for?
Sign up for free today!

Related Links:
- Read more on the mathematics of online research
- Featured Survey Articles Listing