“Sign up” or “Membership”? “Donate Now” or “Donations”?
You can create an action button with verb or a noun. Is there any recommendation for increasing the click-rates? Which one is better than the other for having more clicks?
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Christopher Bryan and Gregory Walton (2011) conducted a study for understanding if using a noun or verb statement have an influence on user motivation. According to the results of their study, participants in noun group expressed significantly more interest, 62.5%, in registering vote than participants in the verb group, 38.9%.
Another study about "help" and "being helper" among children validates their hypothesis also with kids
Take-aways from their interconnected studies :
All of your examples are verbs: sign, register, donate, be
Regarding click-rates; any answer given will be results for a different user base. The only way to truly know what is more successful for your use case would be to do A/B testing with your users, and study the metrics/measures related to your site. Perhaps you could use general statistics if it applies (as a starting point), but keep in mind that even the same users are receptive to different phrasing/terminology within different contexts. Psychology is an interesting field.
This is why personas are important. For instance, when executing some command, mathematically-minded individuals may gravitate towards "compute", whereas managers might relate better to "process". It all depends on your users. Even subtle changes in environment may be enough to trigger certain expectations.
The study of Christopher Bryan and Gregory Walton mentioned in another answer is interesting but there is not a universal rule of which is the best.
Sometimes you might want to show immediacy and use verbs.
Some other times you might need to have nouns for things that are related to identity.
The only thing that could help you here is empathy:
Take a glance at your user persona and then speak the phrase of the action out loud and try to put yourself in the shoes of your user.
This way is will be easier to see which option will drive a higher click/tap rate.
Always imho the ux work is hard and try not to use a rule of thumb in all cases.
Following the safe route? Well I have yet to found one in our job :)