Is the following random variable discrete or continuous? Explain why.
The temperature of the water in the Arabian Gulf
Continuous, it is measurable.
What is the area under the curve of all normal distributions?
1
This distribution can be used to approximate probabilities on the binomial distribution (when n is large).
Normal Approximation
Measures of Central Tendency (three)
Mean, Median, Mode
Allow us to compare relative placement of scores
What is a Standard Score?
p =
probability of success on one trial
A uniform distribution (hint: what type of variables are used?)
Discrete Variables
means that between any two data values we could (at least in theory) find another data value.
What is a continuous distribution?
Classifies/identifies objects
Nominal Variable
Applied when considering the area under the curve from this approximation.
What is continuity correction?
q = 1-p
is the probability of failure on one trial
Another name(s) for Normal Distribution
Bell-shaped or Gaussian Distribution
Each normal distribution is defined by....
Mean & standard deviation
Ranking data (distances are not the same)
Ordinal Variables
A statistical tool examining the bivariate relationship between two variables
What is Correlation?
n =
total number of trials
Ex: Outcome of rolling a die (what is the type of variable & distribution?)
Discrete Variable & Uniform Distribution
The interval or range of possible values within which the population parameter’s value is likely to be contained.
Confidence Interval
the average; the balancing point n Sum of values divided by sample size (N)
Mean
Calculating the total number of orderings of a set or subset.
What is Permutation?
r = number of successes
number of successes
Mean = Median = Mode (what is the distribution)
Normal Distribution
Step1: Convert X to z, using the mean and s.d. n
Step2: get the probability for z.
Calculating the probability for a given interval
Rating data (equal distances)
Interval Variables
Name the Correlation Coefficient: IQ and gender
What is Point-biserial correlation? (One continuous variable and one dichotomous variable)