Exam 1 Flashcards
(23 cards)
define conditional probability
the probability that one event happens given that another has already occurred.
which way does the tail of a negative skewed curve lean?
left
which way does the tail of a positively skewed curve lean?
right
define continuous variable
a variable that is measured and can take on a range of values.
define discrete variable
a variable that is counted, and can only be whole numbers (cars in a lot, people in a classroom)
what are these examples of: eye color, blood type, favorite food
nominal scale data
what are these examples of: military rank, grade in school, pain level
ordinal scale data
what are these an example of: time, temperature, credit score
interval scale data
what is a sample
representative subset of a population
what is a population
the entire group you want to draw conclusions about
what is a statistic
data that represents a characteristic of a sample
what is a parameter
data that represents a characteristic of a population
how can types of scale change within an experiment?
transforming data, using different scales for different variables
to be able to determine cause and effect, scientists must…
conduct an experiment
what is the difference between dependent and independent variables?
IV: the probability does not change if another event occurs
DV: the probability does change if another event occurs
what is the difference between standard deviation and variance?
standard deviation = the square root of the variance
what is the difference between a histogram and a bar graph?
histogram: continuous data (ranges), bars touch
bar graph: bars do not touch
p (A or B) = p(A) + p(B) - p(A and B)
Addition Rule
p(A and B) = p(A) * p(BlA)
Multiplication Rule
p(AlB) = p(A and B) / p(B)
Conditional Notation
rank = k/100 (n + 1)
Percentile Equation
population^2 = sigma (x- mean)^2 / number of scores
Variance equation
square root of population^2
Standard deviation
