Transcript Presentation 3 - Dr. Hussein Fahmy

Data Collection
Sampling
Census
Data Collection
Sampling
1. sample intended to be a part of
any group .
2. Costs for sampling is acceptable.
3. Does not need a huge effort .
4. Accurate data that can be
easily analyzed .
5. This method is used in all types
of quality control in production.
Census
1. Can be used in a limited community
and difficult to use in a large
community.
5. Takes a long time .
6. High costs .
7. Identification of a large number
of researchers .
8. The large amount of data and the
difficulty of analysis .
Elements of statistical
design of samples
Choosing the type
of sample
There are many types in the
sample selection and the
researcher must select the
appropriate type.
Search Framework
Are records, files and statistics
data, which include all
the items .
The framework should be
Comprehensive, new and
accurate .
SAMPLES
 Non Probability Samples
- Are Samples that does
not obey the probability
rules specific characteristics
and quality are chosen according
to some specific standards
assumed by the researcher.
 Probability Samples
• Randomly simple samples.
•
Stratified random samples.
• Systematic random samples.
• Group samples.
• Area samples.
Random Samples
Are sample which each individual of the society of research has the
same chance in being chosen in the sample.
These are divided into:
A. Randomly simple sample
Are the ones chosen so that every individual of the society individuals
has equivalent chance in being chosen and this process is unbiased
C. Stratified random samples
It is represented for all categories, classes, and area in the society needed to be
measured. It is done by choosing individuals from each area ( a-b-c-d ) or
from categories or classes in a precise percentage.
Every individual is chosen in a randomly way from these categories to
increase the probability of representing each one of these groups in the
chosen sample.
C. Systematic random sample
Are chosen by dividing a number of society individuals on sample
individuals and the result is called “ survey range ” .
Sample range = 100/10 = 10 these numbers 2 ,12 ,22 ,32 etc…are
chosen
It is used in investigation concerning opinions in air planes
passengers, movies watchers, supermarkets …. Etc
Groups sample:
it is done by choosing a sample of groups ( students – doctors –
employee).
E. Area sample:
Used when for samples that represents different geographical area and
the geographical areas are chosen in a randomly or non-random
way.
Research Tools
Each of the observation, personal interview, survey,
testing, and the case
study are important tools used in research in general,
However, in most of the research, we find that all of the
interview and the survey are used widely, particularly in
the area of research and management and can be divided into
The Most Important Research Tools
Questionnaire
Interview
Observation
Observation
The concept of observation in the scientific research, means
to use observation as a tool for scientific data collection.
This is done through the observation of the subject of
discussion and studying its behavior without
interference from him personally .
Importance of observation
1. Observations are important in descriptive research.
2. The observation method is used in many Applied Science.
3. The researcher can observe personally the subject to be studied.
4. The experience of the researcher affects the existing
Observation significantly in practical terms:
 Affect the stability of the data.
 The selection of the theoretical basis and the Conduct.
 Affects the accuracy of the estimation .
TYPES OF OBSERVATION
• Declared Observation :where the group, which will be
observed, should be notified by the researcher in
advance that the observer will be introduced to them
.with this type of observation the behavior of members of
the group under observation is affected due to the
presence of a noticeable person among them.
• Hidden (invisible) Observation :is the process of
observation, without the knowledge of members of the
group, which are beneficial of an observer
• Participation Observation :it is carried out through the
involvement of the researcher in one of the committees
of personnel of the group or share officially in some other
activities.
TESTING CONCEPT
• The concept of testing in scientific research, means the use of a list
of questions to measure the capabilities of individuals under test, or
measure the level of intelligence or any other things.The
considerations that must be taken into account in the preparation of
a test are:
• Researcher identifies the origin, for which he suggests a test.
• He should select the test which accommodates all dimensions of
the problem.
• He should take into account the appropriate wording of the
questions.
• Researcher sets time limits for the application of the appropriate
test.
• Researcher should examine the reconnaissance sample to make
any adjustments.
Certified Conditions for The Success of a Test
A. Objectivity:
1 - The question should have only one solution ( no debates on solution ) .
2 - The question should have one and only meaning .
B.
Reliability :
1 - Should give the same result when replicated .
2 - Factors affecting the stability of a test :
A ) Length of test .
B ) Degree ( level ) of difficulty .
3 – Methods to identify the degree of stability :
A )The reliability of the test .
C.
B ) To make two different copies carrying
the same meaning .
Validity :
1 - The method of evaluation of a test should be tailored for this actual test .
2 - Nature and aim of the research identifying the degree of honesty accuracy
and level .
3 – Types of Validity:
A) apparent honesty .
B) Internal honesty
D) Forecasting honesty .
C) Replicable honesty
The Types of Interview
Diagnostic
interview
The concept of
the interview .
The considerations that must be observed by the
researcher while interviewing
A-The aim and objectives of the interview should be
identified and prepared in terms of :
1.The time and the right place, for contacting the
individuals.
2.The identification of persons (individuals), which will be
met by the researcher.
B-A plan for an interview must be developed in terms of
the questions (the timing, order and nature).
C-The interviewer needs certain skills such as (to create a
cordial atmosphere appropriate for the interview and the
ability to talk and ask questions clearly.
D-Researcher should have the ability to verify the
authenticity of the statements given in the talk.
E-The researcher must record data and information
obtained during or immediately after the interview.