Module 2: Stats Flashcards
What are the 5 stages of the research process?
- Observation
- Operationalize variables (how do we quantify them?)
- Hypothesis
- Design
- Collect data, analyse, conclusions
What is validity and reliability?
Validity: whether the measure reflects the thing we want to measure
Reliability: same or similar numbers with repeated experiments
What are the six types of variables and what are they?
Categorical: limited number of possible values (%)
Nominal: values have no meaning or order of sequence (categorical with numbers assigned)
Ordinal: values have a meaningful order (eg. Year level)
Quantitative: numerical value is meaningful (interval or ratio)
Discrete: cannot take on all values within the potential limits (no decimals)
Continuous: can take any value
What are the three measures of central tendency?
Mode: most occurring value (can be bi-modal)
Median: middle value (not affected by outliers)
Mean: arithmetic average (whole set of data)
What are the three measures of variability?
Range: max – min
IQR: difference between the 75th and 25th percentile (resistant to outliers)
Standard deviation: how far from the average, how much scores spread out from the mean
What is a p-value?
effect REAL or due to chance? 0.03 = 3% chance that we might see a difference as large or larger in the population if there were really no effect (null hypothesis is true), therefore we can reject null hypothesis and effect is probably real because p-value is small
What is an effect size determined by?
Determined by the difference between the means of groups divided by the average standard deviation
What do the variables do in a negative and positive relationship?
Negative: as one variable increases, the other decreases
Positive: as one variable increases, so does the other
Correlation does not imply….
causation
What do box plots need?
Box plots need; max, upper quartile, median, lower quartile, min
A bar graph skewed to the left will show more values on the left/right side?
right
