Hard Level 1 Flashcards
Sampling techniques
SRS - names in a hat
Stratified - split in population into homogeneous groups, select from an SRS from each group
Cluster - split the population into groups (clusters) and randomly select whole clusters as the sample
Census - entire population
Convenience sample - selects individuals easiest to reach
Voluntary response - people choose themselves by responding to a general appeal
Types of chi squared tests
GOF - use to compare the distribution of a categorical variable in one population to a hypothesized distribution
Homogeneity - use to compare 2+ populations or treatments
Independence - use to test the association between two categorical variables in one population
Binomial setting and random variable
Binary? Each trial classified as fail/ success
Independent? Trials Must be independent
Number? The number of trials must be fixed in advance
Success? The probability of success must be the same for each trial
BINS
4 step process
Confidence intervals
STATE: what parameter do you want to estimate and at what confidence level
PLAN: choose appropriate inference and check conditions
DO: if conditions met, perform calcs
CONCLUDE: interpret interval
Conducting a simulation
STATE: ask a question about some chance process
PLAN: describe how to use a random device to simulate one trial of the process and indicate what will be recorded at the end of each trial
DO: do many trials
CONCLUDE: answer the question of interest
4 step
Significance tests
STATE: what hypotheses do you want to test and at what significance level? Define parameters
PLAN: choose appropriate inference methods
Check conditions
DO: if conditions met, perform calcs
Find test stat and p value
CONCLUDE: make decision about the Ho, Ha
Experimental designs
Completely Randomized Design - units are allocated at random among all treatments
Randomized Block Design - units are put into homogeneous blocks and randomly assigned to treatments within each block
Matched Pairs - a form of blocking in which each subject receives both treatments in a random order or subjects are matched in pairs with one subject in each pair receiving each treatment, determined at random
