Stats test 1

Question 1

Population

Answer 1

consists of all individuals or objects of a particular type

Question 2

Descriptive statistics

Answer 2

consists of procedures used to organize and summarize the important characteristics of a set of measurements

Question 3

Inferential Statistics

Answer 3

allows us to draw conclusions based on information contained in a sample

Question 4

Probability

Answer 4

forms a bridge between descriptive and inferential stats and gives us an understanding of the properties of a population based on its distrubtion (deductive reasoning)

Question 5

Steps of Hypothesis test

Answer 5

1.) determine parameter 2.) formulate null hypothesis 3.) determine test statistic 4.) From Ha 5.) set alpha 6.) compute 7.) determine Reject or DNR

Question 6

Type 1 Error

Answer 6

rejecting the null hypothesis when Ho is true

Question 7

Type 2 Error

Answer 7

Accept null hypothesis when Ho is false, denoted by beta

Question 8

P value

Answer 8

the smallest level of significance at which Ho would be rejected, the smaller the value the more contradictory it is to Ho

Question 9

P values for z test

Answer 9

Upper (1- phi(z))
Lower phi(z)
Two tail 2[1-phi(|z|))

Question 10

Pooled t

Answer 10

two populations that are normal with equal spreads, determining if centered on same place

Question 11

Testing Proportions

Answer 11

p hat (sample proportion) n*Po >10 and n(1-Po)>10 for test to be valid

Question 12

Confidence Interval

Answer 12

range where parameter is expected to fall, it is the measure of the degree of reliability of the interval

Question 13

Interpretation of CI

Answer 13

95% of all confidence intervals constructed will cover the true mean

Question 14

Precision of CI

Answer 14

increase n, to make interval smaller, making alpha bigger will result in a bigger CI

Question 15

Margin of Error

Answer 15

based only on sample size

Question 16

T curve and Z curve

Answer 16

Z curve is a t curve with infintie degrees of freedom

Question 17

Factor

Answer 17

a variable that is being changed and results observed

Question 18

Level

Answer 18

a value that is assigned to change the factor (I)

Question 19

Treatment condition

Answer 19

the set of conditions for a test in an experiment (factors and their levels

Question 20

Replicate

Answer 20

a repeat of a treatment condition (J)

Question 21

Randomization

Answer 21

treatment conditions are run in a chance order to prevent any build up of results

Question 22

Orthogonal array

Answer 22

a simple way of putting together the treatment conditions so that the design is balanced and factors can be analzed

Question 23

Interaction

Answer 23

two or more factors that together produced a result different than their separate effects

Question 24

Assumptions

Answer 24

I treatments have distrubtion N(mean, variance) with similiar variances their sum is 0, Each Xij is normal and IID,

Question 25

Evil error

Answer 25

random error, dont know where it came from (eij)

Question 26

Alpha i

Answer 26

deviation- spread from mean

Question 27

Alternative description of ANOVA

Answer 27

Xij= mu+alpha(i)+ eij

Question 28

Fixed Effects

Answer 28

alpha