Statistics III

Question 1

Descriptive Statistics

Answer 1

Describe how many observations were recorded and how frequently each score or category of observations occurred in the data

Question 2

inferential statistics

Answer 2

makes predictions about a population based on a sample of data taken from the population in question

Question 3

2 types of statistics

Answer 3

Descriptive

Inferential

Question 4

Inferences are based on _____

Answer 4

probability

Question 5

In statistics, what is considered ‘significant’ p values?

Answer 5

p

Question 6

what are the Two types of Inferential Statistics?

Answer 6

Comparative statistics

Regression statistics

Question 7

What are the two types of Hypothesis testing?

Answer 7

null hypothesis Ho

alternative hypothesis Ha

Question 8

What is Ho?

Answer 8

negative statement or no difference b/w two means

Question 9

What is Ha?

Answer 9

alternative hypothesis or there is a difference bw/ two means

Question 10

4 types of variables?

Answer 10

Nominal/categorical
ordinal/ranked
interval/numeric
ratio

Question 11

What is nominal/categorical data?

Answer 11

Data that have names or arbitrary numeric assignments, unordered categories
Yes, No. Race/ethnicity, gender

Question 12

What is ordinal data?

Answer 12

Data that can be arranged in ascending or descending order

Highest level of education, survey questions (disagree>neutral>agree) income categories

Question 13

What is interval data?

Answer 13

Data with no true zero

Temperature, percent change

Question 14

What is ratio data?

Answer 14

Numbers on a scale with a meaningful zero.

Height, weight, cholesterol levels

Question 15

Two types of variables in hypothesis testing

Answer 15

Independent vs. dependent

Question 16

What is Independent variable?

Answer 16

Variable that is systematically manipulated by investigator to show the effect on the outcome of experiment
changing diet to show body weight outcome

Question 17

What is the dependent variable?

Answer 17

Response that is measured as a result of the independent variable
Variable likely to be though of as a different by the researcher

Question 18

________ is based on the probability of a chance

Answer 18

Significance

Question 19

What are the basic properties of Probabilities?

Answer 19

Property 1: probability of an event occurring is always b/w 0 and 1(0%-100%)
Property 2: the probability of an event that cannot occur is 0 (i.e pigs flying)
Property 3: The probability of an event that must occur is 1 (ie. sun rising in the east)

Question 20

p

Answer 20

reject the null hypothesis

Question 21

p>α

Answer 21

fail to reject the null hypothesis

Question 22

Test decisions with ___________

Answer 22

confidence intervals

Question 23

The probability that a particular value lies within this interval is called a _________

Answer 23

level of confidence

Question 24

Confidence intervals are used with 2 types of tests

Answer 24

Odds ratio OR

Rate Ratios RR

Question 25

CI that does not overlap 1 is equivalent of a p value of ____

Answer 25

p<0.05

Question 26

If CI overlaps 1, that is equivalent to a p value of ____

Answer 26

p>0.05

Question 27

2 categories of a test

Answer 27

parametric | non-parametric tests

Question 28

what is a parametric test?

Answer 28

assume that the variables have a particular distribution (normal distribution) to assess the p-value of the outcome typically used for ratio and internal variables

Question 29

What is a non-parametric test?

Answer 29

typically used for ranked variables, categorical variables or when the distribution is not normal (skewness)

Question 30

What is a T-test?

Answer 30

useful statistical test that determines whether there is a difference b/w two means is significantly greater or lesser than would be expected based on the populations. Can only assess one variable at at time!!!!

Question 31

What is a Chi Square test?

Answer 31

measures the differences bw what is observed and what is expected according to an assumed hypothesis

Question 32

T- Test analyses _____

Answer 32

continuous data

Question 33

Chi-Square analyses _____

Answer 33

categorical data

Question 34

What is correlation?

Answer 34

allows us to measure the relationship b/w two or more variables

Question 35

Two types of correlation ests

Answer 35

pearson (parametric) | spearman (non-parametric)

Question 36

r=_______

Answer 36

correlation coefficient

Question 37

If the r is close to -1, then there is a _________

Answer 37

strong negative correlation

Question 38

If the r is close to 0, then _________

Answer 38

there is no linear relationship

Question 39

If the r is close to +1, then there

Answer 39

is a strong positive correlation

Question 40

What is regression?

Answer 40

Test to see if we can predict an unknown variable's value based on the value of a known variable or variables

Question 41

If outcome is is continuous, then there is one independent variable with 2 group, use _____

Answer 41

t-test

Question 42

If outcome is is continuous, then there is one independent variable with 3+ groups, use ____

Answer 42

ANOVA

Question 43

If the outcome is continuous and there is more than one independent variable use ____ if all independent variables are categorical

Answer 43

ANOVA

Question 44

If the outcome is continuous and there is more than one independent variable use ____ or multiple linear regression, if only some independent variables are continuous

Answer 44

ANCOVA (analysis of covariance)

Question 45

One way ANOVA

Answer 45

used to compare the mean values of continuous variables among independent groups

Question 46

Two way ANOVA

Answer 46

way of studying the effects of two factors separately and/or together