Module 3

Question 1

parameter

Answer 1

any characteristic/calculation of a population

Question 2

statistic

Answer 2

• any calculation/calculation of the sample
• used to estimate population parameter
• differences between sample groups are called sampling vairablity

Question 3

standard error of mean

Answer 3

• looks at the difference of each sample mean and the pop mean
• greater means data has lots of variability
• calculated using the population and sample size
• SEM error bars used when sure of the pop mean

Question 4

standard deviation

Answer 4

looks at the difference between observations and the sample mean

Question 5

random variables

Answer 5

any measurable/categorized characteristic where values/outcomes depend on chance, visualized by probability distributions

Question 6

binomial distribution

Answer 6

discrete, dichotomous, mutually exclusive with a fixed number of independent trials

Question 6

types of probability distribution

Answer 6

binomial distribution
poisson distribution
guassian (normal) distribution

Question 7

poisson distribution

Answer 7

binomial event but events occur infrequently with no restrictions on the number of trails

Question 7

gaussian (normal) distribution

Answer 7

continuous variables with infinite number of outcomes
- pop mean = 0
- pop SD = 1

Question 7

z score

Answer 7

• represents the number of SD between random variables and the pop mean
• calculated using variable, pop mean and pop SD
• used to calculate the probability of variables occurring in certain ranges

Question 7

empirical rule

Answer 7

• the probabilities associated with each range for normal distribution
• occurs one, two or three SD of mean

Question 8

central limit theorem

Answer 8

as sample size increases all sampling distributions will approximate the normal distribution
- mean approximated pop mean
SD = standard error

Question 9

estimation

Answer 9

estimates a pop parameter using sample statistics and probablity

Question 9

hypothesis testing

Answer 9

making decisions about a value of a pop parameter using a sample of data and probablity

Question 10

interval estimation

Answer 10

range of values likely with the population parameter
- CI, 95% confidence true pop falls within range

Question 11

point estimation

Answer 11

single value (sample mean) used to estimate pop parameter

Question 12

confidence interval

Answer 12

95% CI falls within +/- 2 SD

Question 12

hypothesis testing decisions

Answer 12

fail to reject the null - not enough evidence to suggest differences (p greater than 0.05)
reject the null - evidence suggests differences (p less than 0.05)

Question 13

null hypothesis (H0)

Answer 13

status quo, no difference

Question 13

alternative (H1)

Answer 13

differences, can be one tailed (upper or lower) or two tailed

Question 14

significance level

Answer 14

the risk willing to take that findings are incorrect (5% chance of incorrect)

Question 15

rejection region limit

Answer 15

two tailed 5% split (2.5% upper and lower), one tailed 5% all on one side

Question 15

type I and II error

Answer 15

type I null is true but you reject the null, type II null is false but you accept the null