PSY 217: Final Exam Review

"Concepts of a Plan"

100

A confidence interval is a(n) _____ that includes the population mean a certain percentage of the time if the same population is sampled from repeatedly.

Interval estimate

200

Which "branch" of statistics uses numerical observations and incorporates them into an organized and informative summary of the data?

Descriptive

300

Fill in the Blank: 

1.) A _______________design has different people in each group and can be analyzed using an Independent Samples t Test. 

2.) A _______________ design has the same people in each group and can be analyzed using a Paired Samples t Test. 

1.) Between-Subjects/Groups

2.) Within-Subjects/Groups

400

Rita wants to compare young children's reading test scores across three instructional conditions: phonics, whole language, and one control group (no instruction). What type of statistical test should she use?

ANOVA

500

Scatterplots are often used to assess what type of pattern the data create between two variables. For example, when the data form a pattern that flows downward and toward the right in a straight line, this is considered to be a(n):

negative linear relation

It's not Rocket Science...it's just Normal Distributions

100

Normal distributions are described as: 

1. _______________

2. ________________

3. ________________

1. Unimodal

2. Symmetrical 

3. Mathematically defined 

200

Below or Above? 

A negative skew may have a tail that indicates extreme scores _____ the center of the distribution.

Below

300

In a _________ skewed distribution, the tail of the distribution extends to the right.

Positively

400

A standard deviation is equal to 6.40. This number means that the numbers in the sample deviates ____________________ from the mean. 

6.40 units from the mean.

500

Use your whiteboard, this question gets 90 seconds: 

Draw a normal curve and plot the critical values of a z-test. Label the space within and outside of the critical values with the appropriate decision phrases. 

Critical values for a z test: -1.96 and 1.96

Within -1.96 and 1.96: "Fail the Reject the Null Hypothesis" 

Outside of -1.96 and 1.96: "Reject the Null Hypothesis"

Equations or Brain Rot?

100

_____ is the symbol that represents standard error (population).

𝜎_M

200

The equation z(𝜎) + µ is used to convert a _____ to a _____.

z score to a raw score

300

Jillian wants to see if there is a difference between the U.S population of coffee drinkers (µ = 3.1, 𝜎 = 0.9) to a sample of 34 coffee drinkers at a local coffee shop (M = 3.8). What equation would be of most use to her?

 Please write the equation on your whiteboard. 

z = M - µ / 𝜎_M

400

Which equation is the correct formula for the t statistic?

M - µ / s_M

500

This question gets 120 seconds: 

George wants to conduct an independent samples t test. The value for the standard error for the difference between the means (s_M) is 2.45. Group A has a mean of 14 (M_X), and group B has a mean of 17 (M_Y). What is the value of t?

t = -1.22

Calculations are my friend :)

100

This question gets 120 seconds:

Here is a list of datapoints: 

1, 3, 3, 3, 4, 6, 12, 16, 24, 27 

Please calculate the Mean, Median, & Mode

Mean = 9.9

Median = 5

Mode = 3

200

This question gets 90 seconds:

Here is a list of datapoints: 

1, 3, 3, 3, 4, 6, 12, 16, 24, 27

Calculate the Range

Range = 26

300

This question gets 120 seconds:

Here is a list of datapoints: 

1, 3, 3, 3, 4, 6, 12, 16, 24, 27

Calculate the Interquartile Range

Q3 – Q1 = 17

400

This question gets 120 seconds: 

The Mean of the dataset from prior questions is M = 9.9. Please calculate the appropriate values for scores (X) 1 and 3. Use prompt below: 

X                X – M                   (X – M)²

1                    #                           #

3                    #                            #

X                X – M                   (X – M)²

1           1-9.9 = -8.9          (-8.9)² = 79.21

3           3-9.9 = -6.9          (-6.9)² = 47.61

500

This question gets 90 seconds: 

The sum of squares has been calculated for all of our data points of interest. We calculated a value of 804.9 as our sum of squares for a sample of 10 datapoints (N = 10). Please calculate the standard deviation.

sq root of 804.9/ 10 = 8.97

z, t, & F

100

When attempting to find a percentage associated with a particular z score, an important step involves looking at a:

z  table

200

The critical value(s) associated with a p level of 0.05 for a two-tailed hypothesis test using the z statistic is (are):

-1.96 and 1.96

300

To conduct a single-sample t test, you need:

(A known population and sample mean and) an unknown standard deviation of the population (𝜎 )

400

F is obtained by dividing _____ by _____.

MS_between; MS_within

500

This question gets 120 seconds: 

What is the paired-samples t statistic when using M_difference = 8.0, s = 9.3, N = 24?

t = 4.21