Exam 1 Content

Question 1

Nominal Scales

Answer 1

classified into one of the categories and then counted for frequency

Question 2

Ordinal Scales

Answer 2

gives quantitative order to variables (rank order scale)

Question 3

Interval Scale

Answer 3

equal intervals of measurement

Question 4

Ratio Scale

Answer 4

based on order, has equal distance between scale points, and uses zero to represent the absence of value

Question 5

Null Hypthoesis

Answer 5

predicts no difference between groups (x=z)

Question 6

Alternate Hypothesis (research hypothesis)

Answer 6

predicts a difference between groups

Question 7

Independent Variable

Answer 7

manipulated by researcher

Question 8

Dependent Variable

Answer 8

the outcome

Question 9

Statistical Inference

Answer 9

process of generalizing from a sample to a population

Question 10

Population

Answer 10

a group of things that all have at least 1 common characteristic

Question 11

Sample

Answer 11

portion of population

Question 12

Central Limit Theorem

Answer 12

states that the sum of random numbers become normally distributed as more numbers are added

Question 13

Mesokurtic Curves

Answer 13

frequency tapers off symmetrically towards the tail

Question 14

Platykurtic

Answer 14

thinner and longer tails than normal distribution (longer)

Question 15

Leptokurtic

Answer 15

less tails than normal distribution (higher)

Question 16

Skewness

Answer 16

measure of bilateral symmetry

Question 17

Equation for Skewness

Answer 17

(Sum of Z^3)/N

Question 18

Kurtosis

Answer 18

Measure of the relative heaviness of the tails

Question 19

Equation for Kurtosis

Answer 19

(sum of Z^4/N)-3.0

Question 20

Standard Error Factor for Skewness

Answer 20

SqrRoot(6/N)

Question 21

Standard Error Factor for Kurtosis

Answer 21

SqrRoot(24/N)

Question 22

Positively Skewed

Answer 22

tail to the right

Question 23

Negatively Skewed

Answer 23

Tail to the left

Question 24

Z-Score

Answer 24

raw score expressed in standard deviations

Question 25

X

Answer 25

mean

Question 26

SD

Answer 26

sample mean

Question 27

Sigma or Mu

Answer 27

population mean

Question 28

Z Score Equation

Answer 28

X-X/Sigma

Question 29

Sampling Error

Answer 29

amount of error in the estimate of a population parameter that is based on a sample statistic

Question 30

Standard Error of the Mean

Answer 30

indicates the amount of error that may occur when a random sample mean is used as a predictor of the mean of the population

Question 31

Equation for Standard Error of the Mean

Answer 31

SD/SqrRoot(N)

Question 32

Sampling Distribution of the Mean

Answer 32

frequency distribution of the sample means

Question 33

Equation for Sample Distribution of the Mean

Answer 33

Mu= X +/- 1(SEm) where X=sample mean and Mu=pop mean

Question 34

Level of Confidence

Answer 34

Percentage figure that establishes the probability that a statement is correct

Question 35

Probability of Error

Answer 35

If x is the chance of being incorrect than p<.x

Question 36

Confidence Interval

Answer 36

range of values associated with a level of confidence

Question 37

Equation to find Confidence Interval

Answer 37

Mu = X +/- Z(SEm)

Question 38

Type I Error

Answer 38

Rejected H but it is true (alpha)

Question 39

Type II Error

Answer 39

Accepted H but it is false (B)