Statistical Survey’s

By Shamim RafiqueDirector General Bureau of Statistics Punjab

Statistical Data

• When you measure what you speak and express in numbers, it become data.

• Statistical data is the only measure to reduce too many figures in a simplified form.

• Planning without statistical data may not yield the desired result.

Sources of DataThere are two types of data sources:-

Primary Sources

Censuses

Surveys

Secondary Sources

Institutional sources

Statistical Surveys

Statistical surveys used to gather information by individual. Surveys of human populations and institutions are common in political polling and government, health, social science, marketing research etc.

Statistical Surveys

Survey may focus on opinions or factual information depending on its purpose/objectives:– Survey is called a structured interview or a

researcher-administered survey ,when the questions are administered by a researcher.

– When the questions are administered by the respondent, the survey is referred to as a questionnaire or a self-administered survey.

What is Data?

• Data is a collection of facts, such as values or measurements.

• It can be numbers, words, measurements, observations or even just descriptions of things.

Qualitative vs Quantitative

Data

QuantitativeQualitative

Discrete Continuous

Discrete data can only take certain values (like whole numbers)

Continuous data can take any value (within a range)

{Descriptive information (it describes something)} {Numerical information (numbers)}

Example: What do we know about Arrow the Dog?

Qualitative: He is brown and black He has long hair He has lots of energy

Quantitative: Discrete:

He has 4 legs Continuous:

He weighs 25.5 kg He is 565 mm tall

Collection of Statistical Data

• Data can be collected in many ways: oSimplest way, direct observation, e.g. we

might want to find out how many cars pass by a certain point on a road in a 10-minute interval.

So• Simply stand at that point on the road, and

count the cars that pass by in that interval. • We collect data by doing a Survey.

Census or Sample• Census :Collection of data from every member of

the group (whole "population").• Sample: Collection of data just for selected

members of the group.Example

• 120 people in local football club, everyone (all 120) ask what their age is. That is a census.

Or• Decide, just choose the people that afternoon.

That is a sample.

Errors in sample surveys

Non-sampling errors, caused by other problems in data collection and processing. They include:– Over coverage: Inclusion of data from outside of the

population.– Under coverage: Sampling frame does not include

elements in the population.– Measurement error: E.g. when respondents

misunderstand a question, or find it difficult to answer.

– Processing error: Mistakes in data coding.– Non-response: Failure to obtain complete data from

all selected individuals.

Advantages and disadvantages of surveys

Advantages:• It is an efficient way of collecting information from a large

number of respondents. Very large samples are possible. Statistical techniques can be used to determine validity, reliability, and statistical significance.

• Surveys are flexible in the sense that a wide range of information can be collected. They can be used to study attitudes, values, beliefs, and past behaviors.

• They are standardized and relatively free from several types of errors.

• Relatively easy to administer.• Economy in data collection due to the focus provided by

standardized questions. • Sample surveys are usually cheaper to conduct than a full

census.

Modes of Data Collection

There are several ways of administering a survey, including:Telephone:

Three types: – traditional telephone interviews– computer assisted telephone dialing– computer assisted telephone interviewing

Mail– The questionnaire may be handed to the respondents or

mailed to them, but in all cases they are returned to the researcher via mail.

Modes of Data CollectionOnline surveys:

– can use web or e-mail. Web is preferred over e-mail because interactive HTML forms can be used

Personal in-home survey– respondents are interviewed in person, in their

homes (or at the front door) Personal mall intercept survey

– shoppers at malls are intercepted - either interviewed on the spot, taken to a room and interviewed, or taken to a room and given a self-administered questionnaire

Four Main Classes of Data

• Administrative data.

• Survey data.

• Census data.

• Surveillance data.

Administrative data• Education record.

• Vital registration system.

• Reliable data on IMR, MMR, TFR, CBR & CDR.

• NEMIS.

• HMIS.

• Report of concerned Ministries / Department and Planning Commission.

Survey/ Census Data• Population censuses are carried out in most

countries once every 10 years.

• Inter-censal estimates are produced to keep track of changes in the population in the period between censuses.

• The main advantage of a census is that, everyone is included.

• Censuses generate a sampling frame for future household surveys.

Surveillance Data

• In the area of public health, surveillance is defined

as the ongoing, systematic collection, analysis,

interpretation, and dissemination of data on health-

related events.

• Surveillance data from all of these areas are

essential for developing public health policies and

programmes and evaluating their effectiveness.

Metadata– Metadata provides information on the content,

quality and other characteristics of a dataset. Concept of metadata is to obtain information that help us to interpret data:

• Kind of data collection, Vehicle was used (e.g. survey, census);

• Where and when the collection took place?

• Indicate the sample size and sampling technique;

• Definitions of all the items collected; and

• Who collected the data, and who is responsible for their management?

Institutional Information System

Water & SanitationWater &

Sanitation

Health ServicesHealth Services

Education Services

Education Services

Social ServicesSocial

Services

MunicipalServices

MunicipalServices

Community

Household Survey

Household Survey

What Survey Can Do For Planning Purposes ?

• Shows whether change is happening, and in which direction

• Tells us how big the change has been

• Allows us to decide whether the intervention is having the predicted effect

– Direction

– Magnitude

• Allows us to estimate trend

Sources of DataThere are two types of data sources:-

Primary Sources

Censuses

Surveys

Secondary Sources

Institutional sources

Usually Dissemination made through: Static Form

– Traditional form– Read only Format– Hard copy based– Modern Static form PDF Format

Dynamic Form – Electronic dissemination (CD, DVD, Web, etc.)– that allow

the users to download the data into their own storage devices for further use

Dissemination

Data Collection Agencies

• Federal Level– Pakistan Bureau of Statistics (PBS)– Agricultural Census Organization (ACO)– Population Census Organization (PCO)– National Institute of Population Studies (NIPS)– National Education Management Information System

(NEMIS)

• Provincial Level– Bureaus of Statistics– Health Management Information System (HMIS)– Project Management Information Unit (PMIU) Education

Questionnaires

• Questions (Face to Face interview)

• Measurements

• Observations• Recordings [by Interviewer]

How to Fill in the Household Questionnaire?• Introduce yourself and explain the reason for the

survey, what the questions are about and how you are going to ask them.

• The questionnaire may needs the presence of both male and female members in the household, to ensure best information to the questions.

• Most of the questions have to be answer to by the head of family either male or female. If the head of family is absent, the most informed adult present from the household will be interviewed.

• The questions may relates to health, nutrition, water etc. be asked to the most informed present from the household.

Pakistan Demographic Survey

• Dependency Ratio • Sex Ratio • Household Size• Marital Status • Crude Birth Rates • General Fertility Rates • Age Specific Fertility

Rates

• Total Fertility Rates • Crude Death Rates • Sex and Age Specific

Mortality Rates • Infant Mortality Rates • Neonatal and Post-

Neonatal Mortality Rates

• Expectation of Life

What Data Can Do For Planning Purposes ?

• Shows whether change is happening, and in which Shows whether change is happening, and in which directiondirection

• Tells us how big the change has beenTells us how big the change has been

• Allows us to decide whether the intervention is having Allows us to decide whether the intervention is having the predicted effectthe predicted effect

– DirectionDirection

– MagnitudeMagnitude

• Allows us to estimate trendAllows us to estimate trend

Target 6: Reduce by three-quarters, between 1990 and 2015, the maternal mortality rate

Indicators Definitions 1990-91 2000-01

2004-05 2005-06

2010-11

MTDF Target 2009-10

MDG Target 2015

Proportion of women 15-49 years who had given birth during last 3 years and made at least one antenatal care consultation

Proportion of Women (15-49) who delivered during the last 3 years and received at least one antenatal care during their pregnancy period from either public/private care providers

15 35 50 52 74 70 100

ChangesChanges

How can this snapshot be used?

Gives us a picture of the current status (at different levels of disaggregation if available)

Tells us the magnitude of the challenge of reaching targets.

Provides hard evidence to motivate policy makers.

Helps to quantify the intervention needed.

Helps to build a global picture of current status.

What progress is being made?

Use of Diagrams

Type of comparison Possible diagram

1. Components as part of a whole Pie chart or component bar chart

2. Differences in composition of a whole

Component bar chart, Layer graph, Multiple pie charts.

3. Size of related measurements Grouped bar chart

4. Changes over time in one or more related measurements

Line graph, Vertical bar chart, Pictograms.

5. Relationship between two sets of measurements

Scatter diagram.

Thanks

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