Economics · Ch 3 — Organisation of Data

Raw Data

3.2

Raw Data

Data as first collected are raw or unclassified — disorganised, usually bulky, and awkward to work with. Meaningful conclusions cannot be drawn from them easily because they do not lend themselves to statistical methods until they are organised.

An example is the marks in mathematics of 100 students recorded just as they came in — a block of 100 unordered numbers such as 47, 45, 10, 60, 51, … Asked for the highest mark, you would first have to sort all 100 values in ascending or descending order, a tedious task that becomes far worse with 1,000 students.

Table Table 3.1TABLE 3.1 Marks in Mathematics Obtained by 100 Students in an Examination


47	45	10	60	51	56	66	100	49	40
60	59	56	55	62	48	59	55	51	41
42	69	64	66	50	59	57	65	62	50
64	30	37	75	17	56	20	14	55	90
62	51	55	14	25	34	90	49	56	54
70	47	49	82	40	82	60	85	65	66
49	44	64	69	70	48	12	28	55	65
49	40	25	41	71	80	0	56	14	22

The same problem appears in the monthly food expenditure of 50 households (values like 1904, 1559, 3473, …): finding the average by eye is very hard, and the difficulty multiplies for 5,000 households.

Table Table 3.2Table 3.2 Monthly Household Expenditure (in Rupees) on Food of 50 Households


1904	1559	3473	1735	2760
2041	1612	1753	1855	4439
5090	1085	1823	2346	1523
1211	1360	1110	2152	1183
1218	1315	1105	2628	2712
4248	1812	1264	1183	1171
1007	1180	1953	1137	2048
2025	1583	1324	2621	3676

The scale of the problem is clear from the Census of India, taken every ten years — Census 2001 contacted about 20 crore persons. Such raw counts mean nothing until they are classified by gender, education, marital status, occupation and so on, after which the structure of the population becomes readable.

"It's manageable now!" — the same kabadiwallah, relaxed, with his junk now sorted into neat labelled piles (newspapers, glass bottles, metals).

Drawn by us to help you understand the concept clearly, and verified to make sure it's accurate. For exams, practice from your NCERT textbook's own diagram.

Own-drawn recreation of the NCERT cartoon (p.24), the 'after' companion to the chaos cartoon: the same kabadiwallah, now relaxed, with his junk grouped into neat, separate piles — newspapers, glass bottles, metals — and the caption "It's manageable now!". It illustrates the benefit classification brings: once similar items are grouped, a particular item is easy to locate. Scene and caption are the book's own facts, reproduc …

…

Start your 14-day free trial to unlock the full solution →

← Previous · 3.1Introduction Next · 3.3 →Classification of Data


47	45	10	60	51	56	66	100	49	40
60	59	56	55	62	48	59	55	51	41
42	69	64	66	50	59	57	65	62	50
64	30	37	75	17	56	20	14	55	90
62	51	55	14	25	34	90	49	56	54
70	47	49	82	40	82	60	85	65	66
49	44	64	69	70	48	12	28	55	65
49	40	25	41	71	80	0	56	14	22


47	45	10	60	51	56	66	100	49	40
60	59	56	55	62	48	59	55	51	41
42	69	64	66	50	59	57	65	62	50
64	30	37	75	17	56	20	14	55	90
62	51	55	14	25	34	90	49	56	54
70	47	49	82	40	82	60	85	65	66
49	44	64	69	70	48	12	28	55	65
49	40	25	41	71	80	0	56	14	22


47	45	10	60	51	56	66	100	49	40
60	59	56	55	62	48	59	55	51	41
42	69	64	66	50	59	57	65	62	50
64	30	37	75	17	56	20	14	55	90
62	51	55	14	25	34	90	49	56	54
70	47	49	82	40	82	60	85	65	66
49	44	64	69	70	48	12	28	55	65
49	40	25	41	71	80	0	56	14	22