Stat Exam 1

non directional what you are actually testing no assumption of a relationship there will be no change

something will happen can be 1 tailed (directional) or 2 two tailed (non-directional) informs about level of significance

directional "i think you will say right more often" p vs alpha p <0.05

will just be "different" nondirectional p vs alpha/s p < 0.025

the bigger thing that you are testing "how intelligent are you”

what you are literally collecting "how intelligent are you”

act scores

When characteristics of the resulting samples are systematically different from characteristics of the population

When the distribution of the sample statistics, under repeated sampling from the same population, is centered at the value of the population parameter,

the specific subset of participants you are collecting data from

the entire collection of observational units that we are interested in

measurements/calculations about our sample

measurements/calculations about our population

gives every observational unit in the population the same chance of being selected. In fact, it gives every sample of size n the same chance of being selected.

So, with a ___e of size 10, any set of 10 words is equally likely to end up as our sample.

selecting the most readily available observational units

getting data from a population after divided it into different clusters

: a list of all possible outcomes of a random process.

“the colors of marbles”

the total amount of your observational units

“you have 25 marbles, your _______ is 25”

A in a test of significance occurs when the null hypothesis is true (there was no difference) but we decide to reject the null hypothesis. (you decide that there was a difference) This type of error is sometimes referred to as a false positive or a “false alarm.”

occurs when we fail to reject the null hypothesis (you say that there is no difference) even though the null hypothesis is false (but there was a difference). This type of error is sometimes referred to as a false negative or a “missed opportunity.”

The probability of an event happening is one minus the probability of the event not happening.

• The probability of at least one of several events is the sum of the probabilities of those events as long as there are no outcomes in common across the events (i.e., the events are mutually exclusive or disjoint).

over a large # of trials, the data will slowly turn into .5000

as sample size increases, the distribution of scores will become more normal “the bell curve” & narrower

npi greater than/equal to 10

n(1-pi) greater than 10

both need to be true for you to know that you have a big enough sample

a probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean.

In any distribution, if you standardize it, you can predict the proportion of the scores

1.645

1.960

2.576

3.291

a measure of how dispersed the data is in relation to the mean. Low standard deviation means data are clustered around the mean, and high standard deviation indicates data are more spread out.

from repeated testing a population and using the deviation from each “mean”

the set of values of the test statistic where the null hypothesis is reject. it us beyond the critical value

.025

0.05

your ability to detect a significant result