problem with processing short codes

I am adding code to a plugin that adds a widget and an additional shortcode handler. the shortcode is being recognized and processed correctly however some of the variables are blank. Here is the code

function WPOS_Shortcodes( $attr ) {
		shortcode_atts( array(
				'id' => '',
				'type' => '',
				'data' => '',
				'amount' => '1',
				'rows' => '1',
				'cols' => '1',
				'dsize' => '300',
				'match-all' => '0',
				'hide-price' => '0'
		), $attr );
		return static::display($attr);
	}

	function display( $args ) {
		$widgetContent = '';
		extract( $args );
		$dblink = tep_db_connect();
	    $query = "select p.products_id, pd.products_name, p.products_image, pd.products_url, p.products_price from " . TABLE_PRODUCTS . " p, " . TABLE_PRODUCTS_DESCRIPTION . " pd where p.products_status = '1'";
		if (!empty($id))
		{
		    $query .= " and p.products_id = '" . $id . "' and pd.products_id = p.products_id";
			$product_query = tep_db_query($query);
			$product = tep_db_fetch_array($product_query);
			$widgetContent = '<a href="' . HTTP_SERVER . '/' . STORE_SLUG . '/?slug=' . FILENAME_PRODUCT_INFO . '&products_id=' . $product['products_id'] . '"><img src="' . DIR_WS_IMAGES . $product['products_image'] . '" width="' . $dsize . '" height="' . $dsize . '"><br />' . $product['products_name'] . '</a><br />' . $product['products_price'];
		}
		else
		{

		}
		return $widgetContent;
	}

both of the functions are inside of a class if that makes a difference.
The problem is that dsize is blank so the image is not resized. I was under the impression that the shortcode_atts() call was supposed to set default values when the value isn’t passed to the shortcode. I am only passing the id value to the short code. so if the defaults are set why aren’t they propagating to the extracted variables?