Task 8

Question 1

How do you manipulate an I.v?

Answer 1

You set its values to at least two different values or “levels”

Question 2

What are the two ways you can manipulate a variable?

Answer 2

Quantitatively : changing amount if variable to which each group is exposed (29mg,39mg 3etc)

Qualitatively:. Giving participants in different groups different treatments (Prozac,lexapro,zoloft)

Question 3

What are the three basic types of experimental designs?

Answer 3

Between subjects design

Within subjects design

Single-subject design

Question 4

What does the between subject design consist?

Answer 4

Different groups of subjects are randomly assigned to the levels of your I.v(data is averaged and analayzed)

Question 5

What does the within subjects consist of?

Answer 5

A single group of subjects is exposed to all levels of your I.v (databis averaged and analyzed)

Question 6

What does singles subject design consist of?

Answer 6

Subjects are exposed to all levels of the i.v(like within group design) but you do not average data across subjects instead you focus in changes of Behaviour of a single subject (or small number of individuals) under the different treatment conditions.

Question 7

What is error variance

Answer 7

Variability amongst scores caused by variables other than your I.v (extraneous variables or subject related variables such as age gender etc)

Question 8

What are some sources of error variance?

Answer 8

—Subjects differ in innumerable ways

—Environmentak conditions aren’t absolutely constant

-Same subject varies from moment to moment

Question 9

How can you handle error variance?

Answer 9

Reducing error variance

Increasing the effectiveness of your I.v

Randomizing error variance across groups

Statistical analysis

Question 10

How to reduce error variance?

Answer 10

—>Holding extraneous variables as constant as possible by treating subjects within a group as similarly as possible (eliminate outside distractions , read instructions same way , follow same procedures)

Question 11

How do you increase the effectiveness of your I.v?

Answer 11

—> selecting correct levels of your I.v for the experiment (if it’s too low it might not show an impact on the D.v)

Question 12

How do you randomize error variance across groups?

Answer 12

Randomly assigning subjects to treatment conditions

Resulting in error variance distributed evenly across the groups (canceling itself)

Question 13

How do you use statistical analysis to reduce error variance?for what?

Answer 13

-Estimating the probability with which error variance alone would produce differences between groups at least as large as those actually observed

—inferential statistics is used

— results are statistically significant when probability is low enough

Question 14

What are between subject designs ?

Answer 14

Randomly assigning subjects to groups then exposing each groups to a single level of the i.v

Question 15

What are the types of designs in between subjects design?

Answer 15

The single factor randomized groups design

Matched group design

Question 16

What other two subtypes of designs can be found in the single factor randomized group design?

Answer 16

Randomized two group design

Randomized multi group design

Question 17

What is the randomized two group design?

Answer 17

Randomly assigning subjects to TWO groups to different levels of the i.v and taking steos to hold extraneous variable

Question 18

What are the advanatages of two group design?

Answer 18

—Simple to carry out

—require few subjects

—no pretesting or categorization of subjects

—statistical analysis is simple

Question 19

What are some disadvantages of the two group design?

Answer 19

—you don’t learn much about the nature of the relationship, or function , relating the i and d variables

—almost no sensititivity to the effect of the i.v (if participants differ greatly, difficult to see effect of i.v)

Question 20

What does randomized multi group design consist of?

Answer 20

More than two groups

Question 21

What is a parametric design?

Answer 21

Manipulating the I.v quantitatively

Question 22

What is a non parametric design?

Answer 22

Manipulating the I.v qualitatively (categorical)

Question 23

What is a multiple control group design?

Answer 23

When just one control group is not adequate to rule out alternative explanations of results you use a variation on the single factor multi group design is used one that includes multiple control groups

Question 24

What are matched groups design?

Answer 24

Matched sets of subjects are distributed at random, one per group into the groups of the experiment

Question 25

How are subjects matched in a matched groups design?

Answer 25

On one or more characteristics that the experimenter believes exert influence on the deo Brent variable

Question 26

What is the logic of the matched group design?

Answer 26

Because each of matched subject goes into different groups , the effect of characteristic in which the subjects were matched is distributed evenly across treatments.

Question 27

Any disadvantage of matched groups design?

Answer 27

If matched characteristic has little or no effect on the dependent variable, matching won’t do any good as leads to Loss if statistics power ad reduced ability to detect effect of independent variable

Question 28

What is a matched pairs design?

Answer 28

Matched groups equivalent to the randomized two group design

Question 29

What are matched multi group design?

Answer 29

Matched pair design using multiple levels of a single factor (single factor multi group design) or multiple factors (factorial design)

Question 30

When does a within subject design seem more appropriate?

Answer 30

When your design has more than 3 groups and is increasingly difficult to find three or four or more subjects with equivalent scores on variables or variables to be matched

Question 31

What is a within subject design?(repeated measures design)

Answer 31

When each subject is exposed to all lev la of the independent variable rather than being randomly assigned to one level

Question 32

Advantages of within subjects design?

Answer 32

-Each subject is “matched” with themselves, because they participate in the experiment across all levels of i.v (reduce error variance)

Fewer subjects can be used due to increased power of detecting effect of i.v

Question 33

What are disadvantages of within subjects design?

Answer 33

—more demanding on subjects as each subject has to exposed to every level of the experimental treatment

—carryover effect: precious treatment alters the Behaviour observed in subsequent treatment

Question 34

Sources of carryover effect?

Answer 34

Damn son

Question 35

How to deal with carryover effects?

Answer 35

Counterbalancing

Taking steps to minimize carryover effect

Making treatment order an independent variable

Question 36

What is counterbalancing?

Answer 36

Assigning various tratments of the experiment in a different order for different subjects in order to distribute any carryover effect equally across treatments

Question 37

What are two variations of counterbalancing?

Answer 37

Complete counter balancing

Partial counterbalancing

Question 38

What is complete counterbalancing?

Answer 38

Provides every possible order of treatments and assigns at least one subject to each ordering (practical for experiments with small number of treatments)

Question 39

What is partial counterbalancing?

Answer 39

Includes only some of the possible treatment orders,orders to be used are chosen randomly from the total set and each treatment must appear equally often in each position

Question 40

What is the Latin square design?

Answer 40

Partial Design used to ensure that each treatment appears an equal number of tiles in each ordinal position (ABCD then 4 times e.g)

Question 41

When should you use a within subject design?

Answer 41

—When subject differences contribute heavily to variation in the d.v

-When number of available subjects is limited

—When you wish to assess changes in performance as a function of increasing exposure to treatment conditions.

Question 42

Within subjects vs matched groups design.

Answer 42

Both deal with error variance by attempting to control subject related factors

If correlation between subject variables and dependent variable is weak, use randomized groups design

Question 43

What are the types of within subjects design?

Answer 43

Single factor two level design

Single factor multi level design

Question 44

What is the single factor two level design?

Answer 44

Simplest version of within subjects includes only two levels of the i.v

All subjects receive treatments in one order and half in the opposite order.

Twotreatment means are compared

Question 45

What is the single factor multi level design?

Answer 45

A single group of subjects is exposed to three or more levels of a single I.v.

The order of the treatment is counterbalanced to prevent carryover effects

Question 46

What is the mixed design?

Answer 46

A design that includes a between subjects factor and a within subjects factor

Used to lessen carryover effects unable otherwise to do with just a within subjects design