Rails : How can I get boolean data from radio button? -

i have db tables 'question', 'answer'.(those 2 tables has been related has_many , belongs_to, , nested_form relationship.)

and there user_answer(boolean, default 'false') column in answer table.

i want make this.

1. if user check radio button, user_answer change 'true' value.
2. then i'll compare value in correct column in answer table,
3. and i'll save result in is_correct column in question table.

but don't know how can do. input form.

<h1><%= @survey.name %></h1>  <%= form_tag({:controller => "surveys", :action => "grading"}) %>   <ol class="questions">    <% @survey.questions.each |question| %>    <li>    <strong><%= question.content %></strong>     <ol class="checkbox">      <% question.answers.each |answer| %>        <%= radio_button_tag(answer.user_answer) %>        <%= label("answer_".concat(answer.id.to_s).to_sym, answer.content) %>      <% end %>      </ol>      <hr />    </li>    <% end %>   </ol>    <div><%= submit_tag("submit", :class => "submit") %></div> 

of course, there error. radio_button_tag need 2 parameters. don't know how can do. please let me know.

declare constant in model such as:

status = [['active', true], ['inactive', false]] 

and use options select in views.

<%= f.select :status, options_for_select(user::status) %> 

useful resources:

http://apidock.com/rails/actionview/helpers/formtaghelper/radio_button_tag

http://apidock.com/rails/actionview/helpers/formoptionshelper/options_for_select