Research Analysis Psych Quiz 1 Review

explain the four levels of measurement (PRACTICE QUESTIONS SLIDE #2)

nominal=data is grouped into categories in no specific order (ex:types of therapy)

ordinal=data are placed into categories that can be ordered but distances between values are not known (EX:severity of symptoms)

interval=ordered data w/ equal intervals between values but no true point to 0. (EX:IQ scores)

ratio=like interval data but w/ a true point to 0 (EX:# of correct responses on test)

contrust means

concepts you are studying

operational definiton means (PRACTICE QUESTIONS SLIDE #5)

how that construct will be used/measured in study

Imagine you are testing whether a new therapy method that reduces anxiety more than traditional. Use this example to explain the difference between systematic variance and error variance.

•systematic variance is the part of the change in anxiety scores that are actually due to therapy

•error variance is everything else such a the participant not sleeping well, misreading a question, having an off day, etc.

explain what the theory of measurement is and give an example as well as how this theory relates to systematic error vs random error

•how we turn ideas or traits into numbers that we can study/analyze. Psychologists cant measure things like stress or memory with a scale, using tests to create numbers represent these measures

•ex:you decide to score pizza on a scale of 1-10;you might base the score on crust, toppings, etc.;if your scores are always based on the same rules that=reliable;if your score truly relates to how tasty the pizza is thats valid.

•systematic error=consistent mistake…harms validity random error=unpredictable mistake…harms reliability -the measurement theory helps to design tools that minimize both-

what is reliability and internal vs external reliablility

•yielding consistent results

•internal=split tests in half and correlate halves; is there consistency within the tests

•external=is the test consistent overtime or across situations

explain validity

extent to which the instrument accurately measures what it is supposed to

explain all the types of validity

•face validity:does the test look like it measures what its supposed to; its about appearance not evidence.

•Criterion validity:Does this test relate to something it should be related to?

•Convergent Validity:Does this test agree with other tests that measure the same thing?

•Discriminant Validity:Does this test NOT overlap with things it shouldn't? (EX:A depression test should not show strong results for anxiety if it’s really focused on depression.)

•Concurrent Validity:does the test result match with another known measurement taken at the same time?

•Predictive Validity:succesfully predicts future outcomes

name the three essential properties

1. Manipulate lV: this is to test the effect of a variable

2. Random Assignment:To eliminate pre existing differences

3. Control Extraneous Variables:To isolate the true cause (ex-same test for all participants)

•these 3 properties allow researchers to make strong causal claim