Test 3

a branch of mathematics that involves the collection, analysis, and interpretation of data.

summarize any set of numbers so you can understand and talk about them more intelligibly.

is used to analyze the data after they had conducted an experiment to determine whether the IV had a significant effect

one of the essential characteristics of the typical or representative score.

• an assignment of symbols to events according to a set of rules.
• exp. your grade on a test is a symbol that stand for you performance.

• a particular set for rules used in assigning a symbol to the event in question.
• Nominal Scale
• Ordinal Scale
• Interval Scale

• A scale of measurement in which events are assigned to categories.
• Exp. Furniture: Chair, Desk, Bed,
• Fruit: Pineapple, Watermelon, Peach

• A scale of measurement that permits events to be rank ordered.
• Exp: First, Second, Third, Fourth

• A scale of measurement that permits rank ordering of events with the assumption of equal intervals between adjacent events.
• DOES NOT HAVE A TRUE ZERO.
• Exp. Temperature: 1 degree, 2 degrees: 0 degrees does not mean no temp.
• Scores on a SAT test: scoring 0 on verbal subtest does not mean no verbal skills.

A scale of measurement that permits rank ordering of events with the assumptions of equal intervals between adjacent events and a true zero point.

• the score in a distribution that occurs most often.
• 12, 15, 20, 20, 20
• Mode = 20

• the number that divides a distribution in half.
• First you must rank order the numbers.
• Exp. 56, 15, 12, 20, 17 -----> 12, 15, 17, 20, 56
• Median = 17

• is the arithmetic average of a set of numbers; found by adding all the scores in a set and then dividing the nymber of scores.
• Exp: 12, 15, 18, 19, 16 -----> 12+15+18+19+16 = 80 -----> 80/5= 16
• Mean = 16

Graphical representation of the percentage allocated to each alternative as a slice of a circular pie.

a graph in which the frequency for each category of quantitative variable is represented as a vertical column that touches the adjacent column

• a measure of variability that is computed by subtraction the smallest score from the largest score.
• Exp. 1, 1, 1, 1, 5, 6, 6, 8, 25 ------> 25 - 1 = 24
• Range: 24

a single number that represents the total amount of variation in a distribution; also the square of the standard deviation.

scuare root of the variance

a symmetrical, bell- shaped distribution having half the scores above the mean and half the scores below the mean.

mode

histogram

Variance

A single number representing the degree of relation between two variables.

a hypothesis that says that all differences between groups are due to chance.

the inferential statistical test used to evaluate the difference between two means.

the ability of a number in a specified set to assume andy value

(Na-1)+(Nb-1)

One-tail, directional hypothesis

• evaluates the probability of only one possible outcome
• directional hypothesis

Type II error

Type I error

Accepting the experimental hypothesis when the null hypothesis is true

Accepting the null hypothesis when the experimental hypothesis is true.

The magnitude of size of the experimental treatment.

directional hypothesis

is under the direct control of the experimenter

type II error

the general plan for selection plan for selection participants, assigning participants to experimental conditions, controlling extraneous variables, and gathering data.

• the belief that explanations of phenomena and events should remain simple until the simple explanations are no longer valid.
• Exp. Don't needlessly complicate the question that you are asking.
• Two group design in the most parsimonious

• two
• Control Group and Experimental Group

A stimulus or aspect of the environment that the experimenter directly manipulates to determine its influences on behavior.

A response or behavior that the experimenter measures. Changes in DV should be caused by manipulation of the Independent variable.

Uncontrolled variables that may unintentionally influences the dependent variable (DV) and thus invalidate an experiment.

Differing amounts or types of an IV used in an experiment (also known as treatment conditions)

the two groups differ significantly

in two-group design, the group of participants that does not receive the IV.

a method of assigning research participants of groups that each participants to groups so that each participants has an equal chance of being in any group.

a control techniques that ensures that each member of the the population has an equal chance of being chosen for an experiment.

Groups of participants formed by random assignment.

refers to a contrast between groups of participants how were randomly.

and experiment in which an extraneous variable varies systematically with the IV, which makes drawing a cause-and-effect relation impossible.

A method of assigning research participants to groups so that there is a relationship between small numbers of participants; these small groups are then randomly assigned to treatment conditions

Research participants in two-group design who are measured and equated on some variable before experiment.

an experimental procedures in which research participants are tested or measured more than once.

research participants in two-group design who are naturally related in some way

refers to a contras between groups of participants who were assigned to groups through matched pairs natural pairs, natural pairs, or repeated measures

levels

Random Assignment

natural pairs

repeated measures

matched pairs

large samples are involved

variability in DV scores that is due to the effects of the IV.

• Variability in DV scores that is due to factors other than the IV, such as individual differences, measurement error, and extraneous variation.
• aka within-groups variability

the ability of a number in a specified set to assume any value

an experiment in which the experimenter directly manipulates the IV.

• a research approach in which the experimenter cannot directly manipulate the IV but can only classify, categorize, or measure the IV because it is predetermined in the participants.
• Exp. IV = sex male or female

• the assumption that the variance are equal for the two (or more) groups you plan to compare statistically.
• Exp. .222 well above .05 the variability of the scores of the two groups is similar.

• Occurs when we do not have homogeneity of variance; this means that our two (or more) groups' variances are not equivalent.
• If p value is less then .05 the variability of the scores were not comparable

refers to the statistical test that can tolerate violation of its assumption and still yield valid results.

As scores on on e variable increase, scores on the second variable also increase

as scores on one variable increase, scores on the second variable decrease.

fewer

words and numbers

the general plan for selecting participants, assigning participants to experimental conditions, controlling extraneous variables, and gathering data.

a stimulus or aspect of the environment that the experimenter directly manipulates to determine its influence on behavior.

the belief that explanations of phenomena and events should remain simple until the simple explanations are no longer valid.

• differing amounts or types of an IV used in an experiment.
• (also known as treatment conditions)

groups of participants that receive the IV

groups of participants formed by random assignment

Groups of participant formed by matching, natural pairs, or repeated measures.

a method of assigning research participants to groups so that each participant has an equal chance of being in any group

one of several steps experimenters take to ensure that potential extraneous variables are controlled, including random assignment matching, and so on

An experiment in which an extraneous variable varies systematically with the IV, which makes drawing a cause-and-effect relation impossible.

a potential extraneous variable on which we measured our research participants and from which we form sets of participants who are equal on the variable.

an experimental effect caused by expectation or suggestion rather than the IV.

• a research approach in which the experimenter cannot directly manipulate the IV but can only classify categorize, or measure the IV because it is predetermined in the participants.
• Exp. Sex, male or female

1 and 3

a statistical test used to analyze data from an experimental design with one independent variable that has three or more groups (levels)

This one-way ANOVA uses independent groups of participants.

this one-way ANOVA uses correlated groups of participants.

defining the independent dependent, and extraneous variables in terms of the operations needed to produce them.

variability in DV scores that is due to the effects of the IV

variability in DV scores that is due to factors other than the IV, such as individual differences, measurement error and extraneous variation (also known as within-groups variability)

another term for error variability.

a table that contains the results of ANOVA. Sources refers to the source of the different types of variation

the amount of variability in the DV attributable to each source

the "averaged" variability for each source; computed by dividing each source's sum of squares by its degrees of freedom.

a single number that represents the total amount of variation in distribution; also the square of the standard deviation.

statistical comparison made between group means after fining a significant F ratio.

Matthew not passing his test has nothing to do with Paul not passing his test