調查方法 Survey MethodBack

調查方法

		所有市民對張雲正對任公務員事務局局長的假設投票結果調查皆為電話問卷調查，由嚴格督導下的訪員進行訪問。

		所有調查都是在嚴格督導下由訪員親身進行電話訪問，對象皆為十八歲或以上之操粵語的香港市民。

		各次調查的成功樣本數目都在五百以上。二千年五月份起，成功樣本數目更增加至一千以上，兼且根據香港人口的年齡性別分佈加權調整。

		2014年1月中起，電話號碼抽樣方法是先從通訊事務管理局之香港電訊服務號碼計劃獲取已分配予電訊商的電話字頭，然後以隨機方式從中產生號碼。最後，按照電腦撥打及過往調查記錄，剔除無效號碼成為最終樣本。

		2014年1月中或之前，電話號碼抽樣方法是從住宅電話簿中首先以隨機方法抽取「種籽」號碼，再以加一減一加二減二的方法產生另一組號碼，然後在混合後再過濾重覆號碼，再以隨機排列方式排次成為最後樣本。

		抽取住戶成員的方法是由訪員在成功接觸目標住戶後，用「即將出生日期」的方法由當時在家的成員抽取其中一人進行訪問。

Survey Method

		All surveys Hypothetical Voting on Clement Cheung Wan-ching as the are telephone surveys conducted by interviewers under close supervision.

		All these surveys are conducted by telephone interviewers under close supervision. Target population of these surveys are Cantonese speakers in Hong Kong of age 18 or above.

		The sample size of all these surveys are more than 500 successful cases each time. Since May 2000, it has been increased to more than 1000, and weighted according to gender-age distribution of the Hong Kong population.

		Starting from mid-January 2014, telephone numbers are randomly generated using known prefixes assigned to telecommunication services providers under the Numbering Plan provided by the Office of the Communications Authority (OFCA). Invalid numbers are then eliminated according to computer and manual dialing records to produce the final sample.

		Before mid-January 2014, telephone numbers are first selected randomly from telephone directories as seed numbers. Another set of numbers is then generated by using the plus/minus one/two method. Duplicate numbers are then screened out, and the remaining numbers mixed in a random order to become the final sample.

		Upon successful contact being made with a target household, one member of the household is selected among those present using the "next birthday" rule.