To save time and money, many companies are turning to online market research. Surveys, in particular, can easily be conducted online or over e-mail. The cost of a 200-person, e-mail survey is $2,500 to $5,000. To get the same number of responses from a snail mail survey would cost between $5,000 and $7,000, and phone surveys can run as high as $15,000 [source; Yahoo! Small Business].
The concept of data mining and profiting off that data mining isn't anything new.  And while some companies engage in some rather disreputable practices to do this, Global Test Market seems to be doing just fine with the whole “consent to disclose” thing.  More importantly, in some cases this may help you as some companies will offer to do more specialized product testing once they've identified you as their target demographic.

Amanda Page had serious student debt—$48,000, to be exact. She was working as an adjunct professor at a couple of different colleges, trying to piece together a full time teaching career, and she wasn’t making enough to tackle what she owed. So she started supplementing her income with side hustles like freelance writing, working as a temporary receptionist, and grading math exams online. As she dove into debt and frugality blogs, she came across a new gig: taking paid surveys online.
Wow, This is the first article I’ve ever read that 1. didn’t offer up filling out surveys as a serious way to earn extra cash, and 2. said everything I’ve ever thought about surveys as a side hustle. I don’t know why people keep suggesting this, when as you point out, there are much better side hustles to score serious cash more efficiently. WELL DONE! ;)

Great post! I find it really helpful and I like to try online surveys. I’m actually looking for information about this site that I came across with, it’s called iglobalsurveys.com. have you heard about this? Is this legit? I want to know more about this site before I join. I was hoping if you can give me some idea. Thank you in advance and once again this post is great.
Something unique that MyPoints offers that most other similar companies don't offer is the ability to earn cash back on some in-store purchases at select stores, along with their online paid surveys. Also, although their online store cashback rates aren't the highest in the industry (ironically, Swagbucks beats them on several offers), they do have special offers that other companies don't have, such as a bonus to sign up for Amazon Prime.

The cost of living has continued to rise, while the average salary is still somewhat stagnant when compared to a decade ago, and this is why so many Americans have started to look for ways to earn money at home without having to invest too much time or effort. Family and friends come first, but with paid online surveys, you will not have to cut out any portion of your routine to earn extra money online, as you can instead go through the processes in your sparest of spare time. 
Unlike many sites, Valued Opinions doesn’t offer you the chance to take cash rewards, at the moment limiting users to retail vouchers and gift cards. Electronic vouchers are usually with you within 24 hours but gift cards can take four to six weeks to arrive in the post. Once $10 has been earned, you can claim Amazon vouchers, Macy’s gift cards and Visa promo codes, among many other reward options dependant on your location. Surveys are said to be varied, but the gift card options less so, so check they are for stores you’ll want to shop in before you tot up lots of points.

I have a very serious question I have been a member of InboxDollars for over 2 years they send me emails that say here’s a survey for you and they waste 10 minutes of my time going through it to tell me that I don’t qualify I wrote them and said I gave you all my demographic information please do not send me this and waste my time but they consistently do that.
i belong to onlycash, mommytalk, talkbacksurveys There was a fourth one I joined ….called watch and tell, or something similar…….(they originally had another name) …Somehow I deleted the site, …and cannot find it when searching for it. It was related to the first sites I named. ….I was ready to cash out, …and cannot find it. Anyone know the name?????
Referral program: Referral programs are a common aspect of thousands of websites as they are a great way to get new registered members. As you may already know, some of the biggest e-commerce giants as well as other companies offer rewards and bonuses to users for referring their website to their friends and family. All you have to do is subscribe to their referral program and share a link to your friends.
Like American Consumer Opinion, Harris Poll Online offers cash incentives to people who are willing to log in regularly and complete online surveys and questionnaires. Once you join, you’ll begin earning rewards for each survey you take. Once you earn enough reward “points”, you can turn them in for purchases made on websites like Amazon, iTunes, Home Depot and Walmart. Conversely, you can also turn in your points for movies, books, and home goods ordered straight from the Harris Poll website. Plus, you’ll be entered into a $10,000 sweepstakes each time you complete a survey.
Swagbucks remains popular as they are a reliable site, offering novel ways to earn rewards, including playing games and watching videos. Completing polls and surveys for money takes around 10 minutes each and can make up the bulk of your time on the site. You won’t always qualify, and getting to a late stage in a survey application process and then finding out you’re not qualified can be pretty galling. The slickly designed website is straightforward and pleasing to use and also allows you to make money on your shopping by offering a range of affiliate links. By simply clicking on the Swagbucks link and shopping at sites including Amazon, Walmart and Nike, you will earn points, as those companies are paying Swagbucks to link to them, and you get a share of their fee.
While surveys vary widely in how they are conducted and used, there are a number of components that are common across nearly all surveys. Many of these common features have been studied in extensive detail by survey methodologists, psychologists, statisticians, and many other fields of research. The general process of survey research is outlined in the figure below.
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