Collecting Quantitative Datafinished
Transcript of Collecting Quantitative Datafinished
Identify people and places you plan to Study
This involves determining 1 -individuals
2 -entire organizations ex: schools3 -combination
Decide what type of people or organizations you will actually studyAnd
How many you will need for your reasearch.
Who supplies the information ? Students, teachers, parents and some
combination of these individuals or entire schools.
At this early stage ,you need to decide at what level the data needs to be gathered .ex: indiviuals , family, school ,school district.
This level is referred as the unit of analysis.
Multiple levels such as indiviuals and schools
Or One level such as principals on schools.
Select individuals who are representative of the entire group.
selection of Representative: refers to the individuals from a sample of a population ,enabling you to draw conclusions from the sample about the population as a whole .
Population :a group of individuals who have thesamecharacteristic .
Examples:Populations
All teachers in high schools on one cityCollege students in all community
collegesAdult educators in all school of education
Adult educators in all schools
Sample:A sample of high school teachers
Students in one community college Adult educators in five schools of education in the
midwest.
a target population : the sampling frame A group of individuals or organizations with some common defining characteristic that the researcher can identify to study.A sample :a subgroup of the target population that the researcher plans to study for generalization about the target population.
Researchers decide what type of sampling Depending on three factors:
they seek for their studies Amount of rigorThe characteristics of the target populationThe availability of participants.
The researcher selects individuals from the population who are representative of that population.
1-simple random sampling: The researchers select participants or
units such as schools for the sampleSo any individual has the probability of
being selected from the population .
The intent of simple random sampling is to choose individuals to be sampled who will be representative of the population.
The typical procedure used in simple random sampling is to assign a number to each individual or site in the population and then use a random numbers table, available in many statistics books, to select the individuals for the sample.
Choose every individual or site in the population until you reach your desired sample size .
More convenientBecause individuals do not have to be
numbered and it does not require a random numbers table.Choosing 1 out of 5
Another type of probability samplingThe researchers divide (stratify) the
population on some specific characteristic (stratum)of the population. E.g, females and males.
It is used when the population reflects an imbalance on a characteristic of a sample .
It is also used when a simple random sampling procedure would yield fewer participants in a specific category e.g, females than you need for rigorous statistical
analysis .
1-dividing the population by the stratum e.g, men and women
2-sampling within each group in the stratum e.g, women first and then men.
So that the individuals selected are proportional to their representation in the total population.
A form of probability The researcher chooses a sample in two
or more stagesbecause:The researchers can not easily identify
the population Or
The population is extremely large.The stages :choosing randomly the districts
Sampling randomly within the districts
Select individuals because they are available , convenient, and represent some characteristic the investigator seeks to study.
Two popular approaches :convenience and snowball approaches
The researcher selects the participants because they are willing and available to be studied.
Alternative to convenience sampling The researcher asks participants to
identify others to become members of the sample .
Select as large as possible from the population.The larger the sample, the less the potential error that the sample will be different from the population.Sampling error: the difference between the sample estimate and the true population score.
Provides the means for calculating the size of your sample based on several factors such as confidence in the statistical test and sampling error. T
Two formulas used: Sampling error formulaPower analysis formula
Identification of the participants Procedure of gaining permissionIdentifying the variables in your
questions or hypotheses and finding definitions for them
Considering types of information that will help you asses these variables.
For the purpose of deternmimg what data you need
Operational definition: the specification of how you will define and measure the variable in your study .
Identify types of data that will measure your variables.
An instrument: is a tool for measuring , observing, or documenting quantitative data, e.x: a test, questionnaire, tally sheet, log, observational checklists, inventory or assessment instrument .
Measure achievementAsses individual ability
Observe behaviourDevelop a psychological profile of an
individual Interview a person
To assess an individual's ability to perform on an achievement test, intelligence test ,aptitude test, interest inventory or personality assessment inventory.Drawback:It does not measure individuals attitudesPerformance data may be costly Time consuming to gatherPotentially biased toward specific cultural groups
To measure feelings toward educational
e.g., assessing positive or negative )topics Attitudes toward giving students a choice (of school to attend.Unbiased questionsThey don’t provide direct evidence of specific behaviors.
Selecting an instrument or using a behavioral protocol on which to record a behavior, observing individuals for that behavior and checking points on a scale
that reflects the behavior.(chicklists)To identify an individual’s actual
behavior,
Or personal documents consist of numeric, individual data available in public records.
Examples: grade reportsSchool attendance recordsStudent demographic data
Census information
SurveysGathering interview data
Using databases for analysisProvides an easy ,quick form of data
collectionDisadvatages:
limitation involving the use of listsrvs and obtaining of e-mail addresses .
Limitations of the technology itself. Lack of the a population list.
The questionable representativeness of the sample data.
What am I going to learn about participants from my research questions
What information can you realistically collect?
How do the advantages of data collection compare with its disadvantages?