Watsonにパレート最適な休日の過ごし方を提案してもらう

$endpoint_url = "https://gateway.watsonplatform.net/tradeoff-analytics/api/v1/dilemmas?generate_visualization=false";
$credentials = [
    "username" => "",// コピペする
    "password" => ""// コピペする
];
$credentials_text = "{$credentials['username']}: {$credentials['password']}";

$request = [
    "subject" => "holiday",
    "columns" => [
        // ...
    ],
    "options" => [
        // ...
    ]
];

$ch = curl_init($endpoint_url);
curl_setopt($ch, CURLOPT_USERPWD, $credentials_text);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["Content-Type: application/json"]);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($request));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$result = curl_exec($ch);
curl_close($ch);

$request["options"] = [
    [
        "key" => "1",
        "name" => "山登り",
        "values" => [
            "price" => 3000,
            "time" => 15,
            "energy" => 100,
            "girlfriend" => 0
        ]
    ],
    [
        "key" => "2",
        "name" => "ランニング",
        "values" => [
            "price" => 0,
            "time" => 2,
            "energy" => 50,
            "girlfriend" => 0
        ]
    ],
    [
        "key" => "3",
        "name" => "映画鑑賞",
        "values" => [
            "price" => 3000,
            "time" => 3,
            "energy" => 15,
            "girlfriend" => 0
        ]
    ],
    [
        "key" => "4",
        "name" => "読書",
        "values" => [
            "price" => 1400,
            "time" => 3,
            "energy" => 10,
            "girlfriend" => 0
        ]
    ],
    [
        "key" => "5",
        "name" => "車を買う",
        "values" => [
            "price" => 4000000,
            "time" => 5,
            "energy" => 60,
            "girlfriend" => 0
        ]
    ],
    [
        "key" => "6",
        "name" => "デート",
        "values" => [
            "price" => 15000,
            "time" => 10,
            "energy" => 50,
            "girlfriend" => 1
        ]
    ],
    [
        "key" => "7",
        "name" => "何もしない",
        "values" => [
            "price" => 0,
            "time" => 24,
            "energy" => 0,
            "girlfriend" => 0
        ]
    ]
];

$request["columns"] = [
    [
        "key" => "price",
        "type" => "numeric",
        "goal" => "min",
        "is_objective" => true,
        "full_name" => "お金",
        "range" => [
            "low" => 0,
            "high" => 5000
        ]
    ],
    [
        "key" => "time",
        "type" => "numeric",
        "goal" => "min",
        "is_objective" => true,
        "full_name" => "時間"
    ],
    [
        "key" => "energy",
        "type" => "numeric",
        "goal" => "min",
        "is_objective" => true,
        "full_name" => "体力"
    ],
    [
        "key" => "girlfriend",
        "type" => "numeric",
        "goal" => "min",
        "is_objective" => true,
        "full_name" => "彼女",
        "range" => [
            "low" => 0,
            "high" => 0
        ]
    ]
];