Semakan pada 03:11, 22 Mei 2013

220

Proses untuk memperolehi data statistik daripada dokumen yang tidak dibangunkan untuk tujuan statistik dipanggil pengekstrakan¹. Umumnya, apapun sumbernya, maklumat statistik adalah tertakluk kepada pemprosesan² sama ada secara manual³, mekanikal⁴, elektronik⁵ atau kombinasi kaedah-kaedah ini. Pemprosesan manual tidak melibatkan peralatan yang lebih kompleks daripada kalkulator⁶. Pemprosesan mekanikal menggunakan mesin-mesin penjadualan (224-2) atau mesin-mesin punch card (224-3); pemprosesan elektronik menggunakan komputer (132-2*). Tanpa mengambilkira kaedah pemprosesan, certain jenis-jenis operasi⁷ tertentu perlu dilakukan termasuk menyunting⁸ data, penjadualan (130-6*) dan pengiraan (132-2) dan penyediaan jadual⁹. Kerumitan operasi-operasi ini adalah bergantung kepada kaedah pemprosesan yang digunakan.

221

Penyuntingan data kebiasaannya memerlukan proses pengekodan¹ bagi beberapa entri pada dokumen asas². Skim pengekodan³ menguhubungkan setiap entri dengan keterangannya melalui kod nombor atau huruf tertentu. Buku kod mengumpulkan dan menerangkan kesemua skim pengekodan. Skim pengekodan dibangunkan untuk memudahkan pembahagian data mengikut kumpulan-kumpulan tertentu. Sebaliknya, klasifikasi⁴ adalah semata-mata senarai kod di mana setiap tajuk⁵ diberikan satu atau beberapa nombor. Selepas data dikodkan, ia akan membentuk fail (213-3*) yang boleh ditukarkan kepada borang yang boleh dibaca oleh mesin. Peringkat kedua dalam pengekodan terdiri daripada pembersihan⁶ fail, iaitu menghilangkan ralat melalui kawalan-kawalan kesahan⁷ dan kawalan-kawalan konsistensi⁷; ia boleh jadi kawalan dalaman dalam setiap unit statistik (cf. 110-1) atau boleh terhasil daripada perbandingan antara unit yang berbeza.

222

The edited data are rarely used directly; they are subjected to grouping (130-7) and tabulation (130-6*), and this normally leads to a presentation in the form of statistical tables (131-4). These may be the outcome of sorting¹, either manual or mechanical, resulting in the reorganization of the elements in a set according to predetermined rules, or more simply of a systematic count of the elements presenting a selected characteristic. The choice of elements or of characteristics may be based on the values of one or several quantitative attributes, or on the modalities² of one or several qualitative attributes. Few studies can do without computation, simple or complex, isolated or repetitive, and the computer (225-2) now allows calculation that would have been too lengthy by hand. These capabilities have led to the development of techniques of data analysis³. Deterministic and stochastic models (cf. 730) often require considerable computations, and so do simulations (730-6).

223

Peringkat penyediaan jadual (220-9) adalah untuk menjadikan hasil analisis boleh diperolehi dalam bentuk penyenaraian¹, jadual numerik (131-4) atau carta (155-2), yang mana biasa digunakan dalam statistik deskriptif². Penggunaan komputer grafik³ dan komputer kartografi³ membolehkan penghasilan pembentangan secara grafik dilakukan pada peringkat awalan.

224

Purely mechanical processing (220-4) did not involve the use of electronic equipment¹ which has come to replace the earlier tabulating machines² or unit record machines² and is much more versatile. In most instances the information is coded (221-1*) first, and then transcribed onto punch cards³ by using a keypunch⁴. A card verifier⁵ is a device used to check the accuracy of the punching. These two types of unit record machines remain in common use since the punch cards are still a frequent way of entering data into the computer. The use of other types of unit record equipment such as the card sorter⁶ and the tabulator⁷ has declined. Increasingly, the data are entered directly on magnetic tapes (cf. 226-4) or disks (cf. 226-5) without resorting to punch cards.

225

Kajian demografi banyak bergantung kepada pemprosesan data secara elektronik¹ menggunakan komputer². Istilah perkakasan³ merujuk kepada komponen fizikal, sementara perisian⁴ membekalkan pengguna⁵ dengan cara untuk mengakses komputer. Pakar komputer⁶ terdiri daripada pengaturcara⁷ yang menulis program⁸ yang diterima daripada penganalisis sistem⁹.

226

Komponen perkakasan (225-3) bagi sesebuah komputer (225-2) terdiri daripada satu atau beberapa unit pemprosesan utama¹, memori utama², one or more peranti storan massa³ yang menggunakan pita magnetik⁴ atau cakera⁵ dan suatu set input - peranti output⁶. Komponen perisian (225-4) terdiri daripada sistem operasi⁷, yang bertanggungjawab dalam menguruskan kemudahan⁸ yang disediakan untuk pengguna (225-5) menjana program-program pengguna⁹ dan program-program pemprosesan¹⁰ iaitu adalah programs (225-8) asal yang dibangunkan untuk mengatasi masalah.

227

A user (225-5) can process his problem by writing a program (225-8) in a general programming language¹ such as Fortran, Cobol, Basic or Algol, or a specific language, designed to use the processing programs (226-9) stored in the central memory (226-2) of the computer such as a data base management system² used to create and maintain a data bank², a survey processing program³ or a statistical package⁴. The devices which are used to enter and receive information from the computer can differ according to the mode of processing. In batch processing⁷, the normal input and output units are the card reader⁵ and the line printer⁶. A console⁸ is the normal input and output unit for processing in a timesharing mode⁹. In either instance the entry units may be spatially separated from the computer and processing under these conditions is accomplished by remote terminal¹⁰.

228

Any information processed in a computer (225-2) undergoes three main phases. First, data entry¹ or input¹ which may be done by using punched cards (224-3*) or by using an on line² device such as a keyboard console (227-8). Data which is already stored in the computer may be accessed from either central memory (226-2) or from one of the mass storage devices (226-3) and used as input data. The second phase, processing (220-2), is divided into two main types: numerical processing⁴ and non-numerical processing⁵. Statistical or arithmetic computations are normally the operations contained in the former while data manipulation operations are the focus in the latter. In a third phase, occasionally referred to as output phase, the processed results⁶ or output⁶ may be printed out on the line printer (227-6) or saved as a file on a mass storage device (226-3) for further processing. Results may also be diverted to a plotter⁷ to obtain processed results in the form of a graph or a figure.

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