Z-values, T-values, and the binomial distribution

Question 1

The normal distribution

What is the central limit theorem?

Answer 1

Samples from a size of 30 or more can be approximated by a normal distribution

Question 2

The normal distribution

What is the difference between a sample distribution and a sampling distribution?

Answer 2

Sample distribution: the distribution of individual values within a single sample, representing the observed data points collected from that specific sample
Sampling distribution: the results of all possible samples of a certain size

Question 3

Z-values

What is the z-value?

Answer 3

The z-value is used to specify the relative position of a measured value within a normally distributed population. You can calculate how many standard deviations a found value differs from the mean.

Only when sample is 30 or larger / when the standard deviation is known

Question 4

T-values

What is the t-value

Answer 4

The t-value is designed for smaller samples (<30) and uses degrees of freedom. Also used when you do not know the standard deviation of the population.

Question 5

The binomial distribution

What is the binomial distribution?

Answer 5

For events where there is only 2 opportunities. The two different chances are called the chance of ‘success’ (p) and the chance of ‘failure’ (q). The chance of success is the same for every partial experiment.

Independent, discrete