● Next Wednesday, we will discuss reliability and validity.
● Next Friday, we will review for the exam.
● Homework: Read chapters 8-9 and review sheet, complete review questions (by Friday), study for the
exam, and come to class with questions
● Data - information researchers obtain on the subjects of their research
○ Information that could be obtained systematically and that can be reproduced
○ The key to empirical research is the ability to make inferences on the basis of data
● Instrumentation - instruments and procedures used in collecting data
● Instrument - device used to collect data, used to measure constructs of interest, completed by subjects,
researchers, or informants
○ Can be used by researchers - rating scales, observation forms, tally sheets, performance checklists,
○ Can be used by subject/informant - questionnaires, self-checklists, attitude scales,
personality/character inventories, achievement test (assess knowledge or skill in an area that has
been specifically taught), aptitude tests (assess intellectual abilities that are not specifically taught),
Likert Scale (1-5)
■ Subject - you are studying 5th graders, and the 5th graders provides you with information
■ Informant - you are studying 5th graders, and the teacher provides you with information
■ Can be modified for when subjects are children but you want their own reports (ex: making
questions less wordy and more picture-based)
○ Can be selection or supply items
■ Selection items - true/false, matching, multiple choice, interpretive (better for when you
want a distinct response, like in a quantitative study)
■ Supply items - short answer, essay questions (better for when you want more open
responses, like in a qualitative study)
○ Attempt for unobtrusive measures
■ Many instruments require the cooperation of the respondent in one way or another
■ An intrusion into ongoing activities could change the respondent’s response → to eliminate
this, researchers use unobtrusive measures, data collection procedure that involves
minimal intrusion into the naturally occurring course of events ○ Instruments can come from previous literature - time efficient, have information on validity and
reliability already, supported by findings in empirical literature
○ Instruments can be researcher developed - time consuming, must establish validity and reliability,
must establish empirical support
○ When looking for good instruments that already exist…
■ Review previous literature
■ Search through databases (ERIC, PsycInfo)
○ Guiding questions in selecting an instrument
■ How much does it cost?
■ How easy is it to administer?
■ How long will it take to administer?
■ Are the directions clear?
■ Is it appropriate for the group to whom it is being administered? (consider age, language)
■ Is it easy to score?
■ How are the results interpreted?
■ How does it measure what it is supposed to measure?
■ What type of data do I end up with?
■ Is it reliable/valid?
○ Norm-referenced instruments - provide information about an individual with respect to a group
that they are being compared to
■ Ex: IQ test, state standardized test that compares to others in the same grade across the
○ Criterion-referenced instruments -