Problem Set #2 Terms

Question 1

Alpha

Answer 1

This is the confidence level we use in expressing significance.

We use α=.05
To express significance in our interpretation as p

Question 2

T/F α=.05 is the historical standard (Winzenz)

Answer 2

True

Question 3

What is the alternative hypothesis?

Answer 3

The hypothesis we hope to support in our research, predicting that a significant relation or difference exists between the groups we are comparing.

Question 4

What is known as the opposite of Null Hypothesis?

Answer 4

Alternative Hypothesis

Question 5

In the analysis decision tree explain what if mean if you are only comparing one group

Answer 5

• a one sample t test

- measures the mean and standard deviation

Question 6

In the analysis decision tree explain what if mean if you are comparing two groups…

Answer 6

• r or two-tailed t-test or Wilcoxon
• R test measures DV & DV
• Two-tailed t-test & Wilcoxon measures IV & DV

Question 7

Define Citation

Answer 7

Stat information that appears at the end of any conclusion or interpretation.

t(14) = 2.78, p

Question 8

Cohen’s convention for describing effect, strength, or variance

Answer 8

.0 - negligence, very little, or none (nearly total overlap (90%))

.2 - weak, small, not much (80% overlap)

.5 - moderate, modest, some (50% overlap)

.8 - strong, lots, a large amount (20% overlap)

Question 9

Cohen’s d

Answer 9

Measure of effect size

Question 10

What does Cohen’s d measure?

Answer 10

It measures how much effect the IV has on the DV

Question 11

Confidence level

Answer 11

We are expressing our confidence in the conclusion.

This means the probability our conclusion is wrong is LESS THAN .05.

Question 12

Control group…

Answer 12

We are not manipulating them, we are just letting them be.

Most likely given placebo

Question 13

Critical Value

Answer 13

Value that is the deciding line between normal and deviant in a sampling distribution

Question 14

Degrees of freedom…

Answer 14

of scores in a sample that are free to vary

df

Question 15

Experimental group…

Answer 15

Level of the IV that receives the treatment

Question 16

What is experimental method>?

Answer 16

Allows us to find cause and effect

Question 17

Hypothesis testing

Answer 17

Testing whether a hypothesis is supports by the results of our research

Question 18

What is inferential statistics?

Answer 18

Inferences are conclusions from data.

Question 19

What is the interpretation?

Answer 19

A statement about the outcome of a statistical analysis.

Question 20

Null Hypothesis…

Answer 20

Hypothesis that says no difference or not relationship exists between the groups being compared.

Question 21

p level…

Answer 21

The probability we use to decide on the critical values, or cutoffs, in hypothesis testing.

Question 22

Parametric test

Answer 22

Stat test based on assumptions about population parameters.

Question 23

Quasi-Experimental Method…

Answer 23

IV cannot be manipulated & if we cannot randomly assign them to groups

Variable is a characteristic of the people we are studying, i.e gender.

Question 24

Replication

Answer 24

NORMSDIST(NORMSINV(1-p)/SQRT(2))

Question 25

Research Hypothesis

Answer 25

AKA Alternative Hypothesis

Question 26

Single-group design…

Answer 26

measures only one group of participants

Question 27

Standard error or the mean

Answer 27

Sx of the sampling distribution, which we can approx the stat for samples

Question 28

Statistical power

Answer 28

Probability of being correct when we reject the null hypothesis

Question 29

Statistical significance

Answer 29

Observed relation or difference between two descriptive measures that is unlikely to have occurred by chance.

Question 30

t distribution

Answer 30

Set of distributions that, although symmetrical and bell-shaped, are not normally distributed.

Question 31

t test

Answer 31

One sample t test compares a sample mean to the known population mean u.

Question 32

two-tailed hypothesis

Answer 32

Research hypothesis in which we predict that the groups being compared are related or different, without specifying the direction.

Question 33

Type I Error

Answer 33

Error in hypothesis testing in which we reject the null when it is true.

Question 34

Type II Error

Answer 34

Error in hypothesis testing in which we retain the null when it is false.

If outcome is not significant.

Question 35

z test

Answer 35

Parametric inferential statistical test of the null for a single sample where population mean & variance are known