Chi Square Independence
What was the population for the test?
Squirrels in Central Park
What catagorical variables were compared?
What animal family are squirrels part of?
Rodent family
Experimental Units
Squirrels in Central Park
What categorical variables were compared?
Location (hectares) and fur color
What were the two independent groups?
Squirrels above ground during AM hours and squirrels above ground during PM hours.
Most common squirrel species in NY?
Eastern gray squirrel
Method/Type of study
Observational Study
Hypotheses
H0: The hectare (location) of the squirrel is independent from the primary fur color.
HA: The hectare (location) of the squirrel is not independent from the primary fur color.
Hypotheses
Ho: p1 = p2
Ha: p1 < p2
Name of squirrel in Ice Age (starts with S)?
Scrat
Name of organization that collected our data
The Squirrel Census
Conditions of Test
randomization, 10% condition (if experiment), expected counts >5.
Conditions of Test
Randomization, Independence btwn. the two samples, 10% condition (for each sample), and large enough sample (p hat combined * n1 & n2 both have to be > than 10)
Number of nuts a squirrel can bury in a single season
10,000
Systematic Sampling
Results
Unable to reject null hypothesis. Hectare is not dependent on a squirrel’s primary fur color.
Results
Unable to reject null hypothesis. The proportion of AM squirrels above ground is not less than the proportion of PM squirrels above ground.
3 distinct alarm calls of squirrels?
kuks, quaas, moans
Approximate number of data (from the website)?
3,000