For the selection of predictors in multivariate linear regression with $p$ suitable predictors, what methods are available to find an 'optimal' subset of the predictors without explicitly testing all $2^p$ subsets? In 'Applied Survival Analysis,' Hosmer &amp; Lemeshow make reference to Kuk's method, but I cannot find the original paper. Can anyone describe this method, or, even better, a more modern technique? One may assume normally distributed errors.


Question: Get phones on all members in a customer group
Answer: this code is give you collection of customer in this group.. you can get by this code.    

$customers = Mage::getModel('customer/customer')
                            -&gt;getCollection()
                            -&gt;addAttributeToSelect('*')
                            -&gt;addFieldToFilter('group_id', $groupId);

    $phone=array();
    foreach($customers ans $customer)
    {
       $phone[]=$customer-&gt;getTelephone();
    }