week 4

Question 1

what does the general process of sampling refer to

Answer 1

the manner by which you get ppl to participate in your study

Question 2

two broad categories of sampling

Answer 2

• probability: each member of a population has a probability of being selected, hopes to draw general conclusions (ex simple random, stratified sample, cluster)
• nonprobability: sampling out of convenience (ex purposive, quota, and snowball)

Question 3

when a sample reflects attributes of the whole target population it is _____ and it is ___ when it does not

Answer 3

representative, biased

Question 4

different types of internal validity (8 total)

Answer 4

• content: contents on a test make sense based on what is measured
• face: if it is valid to those that are taking it
• criterion: if its relatable to previous research outcome/criterion
• predictive: accurately forcast future behaviour
• concurrent: if measure is meaningfully related to another
• construct: if it measures a construct/operational definition
• convergent: should relate to past tests that are related to construct
• discriminant: does not relate to scores not related to construct

Question 5

locus of control

Answer 5

• personal beliefs abt causes of what happens to us
• internal: they control what happens
• external: outside forces control outcomes

Question 6

nominal scale

Answer 6

• classify people into one group or another

Question 7

ordinal scales

Answer 7

• sets of ranking, show relative standing of objects/ppl

Question 8

interval scales

Answer 8

• rank order w equal intervals between ordered events
• preferred bc of more sophisticated stat analysis and wider range of them

Question 9

ratio scales

Answer 9

• similar in equal interval and concepts of order from ordinal and interval scales, but add a true point zero
• point zero=absence of attribute measured

Question 10

Descriptive vs inferential stats

Answer 10

descriptive: summarize data collected
inferential: draw conclusions from data

Question 11

mean location formula

Answer 11

mean location= n+1/2
- n=total number of scores in sample

Question 12

____ stats measures mean, median, and mode

Answer 12

descriptive

Question 13

mean, median, mode, and range def

Answer 13

mean: average
median: middle of numbers
mode: most frequent number occurring
range: difference between highest and lowest number

Question 14

interquartile range

Answer 14

• find quartiles 1, 2 and 3
• Q3-Q1=IQR
• useful when you have outliers in your dataset

Question 15

variance

Answer 15

• shows how distributed data is from the mean

Question 16

standard deviation

Answer 16

• estimates the average amount by which scores in sample deviate from the mean score

Question 17

what is the square root of the variance

Answer 17

standard deviation

Question 18

variance vs SD

Answer 18

• variance: data represents entire population
• SD: data represents a sample of scores from population

Question 19

what does a histogram show

Answer 19

• number of times each score occurs or how often scores within a range occur

Question 20

how to make histogram

Answer 20

• find frequency distribution (table that records # of times an event occurs)
• graph it

Question 21

normal curve

Answer 21

• aka =normal distribution
• bulges near middle and is relatively flat at either end
• hypothetical distribution if everyone was tested on same measure
• at the centre is often mean median and mode

Question 22

t or f: majority of events will fall within the first few standard deviations

Answer 22

true

Question 23

what is the purpose of null hypothesis testing

Answer 23

to determine the rate of which results found were due to chance

Question 24

null hypothesis vs alt hypothesis

Answer 24

• Null: aka nothing, H0, no difference between variables
• alt: what you are hoping to find, Ha, difference between variables is found

Question 25

alpha

Answer 25

• (a) = 0.05
• probability of obtaining particular results if no difference is true

Question 26

publication bias

Answer 26

• notion that only statistically significant results get published

Question 27

file drawer effect

Answer 27

• studies finding no difference are less likely to be published

Question 28

NHST

Answer 28

null hypothesis significance testing

Question 29

effect size

Answer 29

• provides estimate of magnitude of difference among sets of scores, taking amount of variability in scores into account

Question 30

__________ is a range of values expected to include population value with a degree of confidence

Answer 30

confidence interval