Question

In the recent 2019 Australian Federal Election, the Coalition Party was elected to reform government for the next three years. This result came as somewhat of a surprise to many political experts, because public polling for many months indicated that the Labor Party was quite likely to win instead. It follows that something has gone wrong with the polling. In fact, some experts are referring to this event as the “Great Australian Polling Failure of 2019”. Possible explanations include:

i) Selection Bias. In the past, the people polled were chosen by sampling from the phone book. However, these days not many people have their number in the phone book and it is becoming more and more difficult to choose who to contact using this method.

ii) Desire to Please. Much of the recent polling is conducted by what is called “RoboCalls”. This is where the call is not conducted by a person, but rather by a prerecorded message that asks a series of questions relating to the election.

Which of these two options do you think could be a better explanation for the Great Australian Polling Failure? Explain your answer in detail.

Answer 1

Because of technological advancement, the landlines are used by fewer people. Most of the Australians now use mobile phones and some of them have more than one mobile phone. As the landline numbers were easily available on the white pages and the mobile numbers do not have such system getting a good sample for the polling has become difficult and the other cause is that nowadays landlines are mostly used by the elderly than the younger generation. The polling sample mostly included people who had fixed landlines. This made the sample biased and became a reason for the "Great Australian Polling Failure of 2019". The main cause is that the selected sample underrepresented the population. The option (i) is a better explanation for this failure.

Answer. i) Selection Bias. In the past, the people polled were chosen by sampling from the phone book. However, these days not many people have their number in the phone book and it is becoming more and more difficult to choose who to contact using this method.