lecture 6 (stats)

Question 1

what is the purpose of a good graph in data analysis?

Answer 1

1. Show the data
2. Induce the reader to think about the data
3. Avoid distorting the data
4. Present many numbers with minimum ink

5.Make large data sets coherent

6. Encourage comparison
7. Reveal the underlying measure

Question 2

What types of plots are available in JASP’s descriptive module?

Answer 2

• Mean and standard deviation plots
• Raincloud plots
• Time series descriptives
• Flexplots

Question 3

How do you create a histogram in JASP?

Answer 3

1. Open JASP and go to the Descriptives section.
2. Drag the desired variables from the left to the right under “Variables.”
3. Click on the “Basic Plot” menu and select “Distribution Plot.”

Question 4

How do you compare the frequency of more than one group in a histogram using JASP?

Answer 4

Use the “Customizable Plots” section and select “Frequency Plots.”

Question 5

What is a box plot and what does it display?

Answer 5

• a box plot displays the median at the center, surrounded by a box that represents the interquartile range (IQR)
• the whiskers show the top and bottom 25% of scores

Question 6

How do you create a box plot in JASP?

Answer 6

Go to the “Customizable Plots” tab under Descriptive Statistics and select the option to create a box plot

Question 7

What is a scatterplot used for?

Answer 7

visualizes the relationship between two variables and helps identify unusual cases that might cause bias

Question 8

How do you create a simple scatterplot in JASP?

Answer 8

Go to Descriptives → Descriptive Statistics → Customizable Plots → Scatterplot

Question 9

What is a split scatterplot, and how is it created in JASP?

Answer 9

• a split scatterplot shows differences between groups (e.g., gender)
• to create one, drag the variable you want to distinguish into the “Split” box when setting up a scatterplot

Question 10

What is a matrix scatterplot and how do you create it in JASP?

Answer 10

• shows the relationship between many pairs of variables
• In JASP, select the variables you want, and under “Basic Plots” in Descriptive Statistics, choose “Correlation Plots.”

Question 11

sample and standard error?

Answer 11

The higher the sample size, the lower the standard error

Question 12

meaning of having a 95% confidence interval?

Answer 12

If we do the experiment over and over again, 95% of the samples will contain the true value

Question 13

effect size?

Answer 13

• size of the correlation between two variables
• the regression coefficient in regression
• a standardized difference