I am experiencing issues with quiz 3 on the topic of correlation. Even though i submited the correct answer for question 7, it marked it as incorrect. My answer was -.67, which is marked as incorrect and stated the correct answer is -0.67.

After installing Gapminder I got an error saying "Error in view(dfSummary(gapminder_df)) : could not find function "view""

Some students are reporting they are unable to get R studio cloud working in the web browser, they are getting a white screen. Is anyone else having this issue? If so, what kind of computer and what browser are you using?

Hi professor,
I spoke to you today (Thursday) about R not working properly, I showed you on my laptop. Many of us are having this issue. Some people can’t even open R. You asked me to remind you to look into it. Please let us know what to do to fix it.
Thanks!

does anyone know how to download R on a Mac. the links he provided has me confused. I downloaded R studio but it doesn't open without R

How do I load csv files into R studio cloud ??

I keep getting "

could not find function "ggplot" as a message on R cloud studio. I'm not sure how to proceed to the next stop if I can't plug in certain codes

I am not sure how to install the data folder. I tried following the video but it isn't showing up on R studio cloud.

Hi

I exported the file on R-Studio Cloud and it saved as a website not a PDF. I uploaded the file as a Google Chrome file.

Is that fine?

I keep receiving the error message below when I try to input the following t-tests:
comparison_df <- all_data %>%
filter(Condition %in% c('Control','Reactivation_only')==TRUE)

t.test(Days_One_to_Seven_Number_of_Intrusions ~ Condition,
comparison_df,
var.equal=TRUE)

comparison_df <- all_data %>%
filter(Condition %in% c('Control','Reactivation+Tetris')==TRUE)

t.test(Days_One_to_Seven_Number_of_Intrusions ~ Condition,
comparison_df,
var.equal=TRUE)

Error message:
Error in t.test.formula(Days_One_to_Seven_Number_of_Intrusions ~ Condition, :
grouping factor must have exactly 2 levels

The table shows scores for and x,y pair of scores, and an a,b pair of scores. Which of the
following is correct about the correlation between x and y, and the correlation betwen a and
b. You should be able to answer this question without computing the correlations.
(a) The correlation between x and y is positive, the correlation between a and b is negative
(b) The correlation between x and y is negative, the correlation between a and b is positive
(c) The correlation between x and y is positive, the correlation between a and b is zero
(d) The correlation between x and y is zero, the correlation between a and b is negative

subjects x y
1 8 7
2 7 3
3 2 6
4 4 2
5 25 27

Anyone know the answer? The numbers seem to be all mixed up (not increasing or decreasing)

Im not able to access the quiz for this week.

I might be incorrect but I believe that one of the questions in the quiz says to find the covariance of a data set using N but the answers calls for N-1.

Compute the correlation between the x and y scores. Report pearson's r to two decimal places (e.g., .14, or .10). Use the formula from chapter 3, make sure you divide by N for all calculations, not N-1. Round your answer up if need be (e.g., .139 should be rounded to .14)

x | y
5 | 4
2 | 1
8 | 5
1 | 2
7 | 9
Selected Answer: 0.8
Correct Answer: 0.8

Answer range +/-0.01 (0.79 - 0.81)Response

Selected Answer: | 0.8
Correct Answer: | 0.8
Answer range +/- | 0.01 (0.79 - 0.81)
Response Feedback: | The correlation between the x and y scores is 0.8

There have been reports that some code from lab 1 is not working in R studio cloud. For example, running the following in an .Rmd file led to a spinning wheel...

library(summarytools)
view(dfSummary(counts))

I'm not sure what is causing this issue. I have been able to run the lab 1 code in R-studio without issues.

Suggestion: make sure your internet connection is working.

I do not know how to properly set up the R markdown files. Is there a file that needs to be downloaded prior to starting the work?

This is what my file looks like.

Is there a way to view or download the slides that are used during lectures?

Hi.

I can't seem to figure out how to submit my lab work. It's due tonight. Any suggestions?

Thank you,
Rachel Tarlow

Is anyone else having problems with not being able to see the quiz #1 we took on blackboard? I can see the attempts I took for every other quiz except that one.

Does anybody know this?

18. Why is it important to check your descriptive statistics against a visual graph of the data?
    (a) The graph shows you whether the descriptive statistics are sensible representations of the numbers
    (b) The descriptive statistics will always be the same regardless of the graph, which is not very important
    (c) The graph will always show that the descriptive statistics make sense for the data, so it is for double-checking a correct answer
    (d) The graph can only show you whether your measures of central tendency are appro-priate for the data, but not measures of variation

How can I add my lab from rstudio into blackboard?

Im not sure why I keep getting this wrong, I entered the answer in positive form (which is what the formula gave me), and I received no credit for the question. I may have used the other formula since there are two in the slides but there shouldn't be any difference because the question explicitly says to enter the answer in positive form.

I am really confused about how to do the generalization exercises of this lab. I believe I have the beginning portion correct but at the end I just can't seem to get it. I messed around with the code as much as I could and I can't attend lab because of the holidays...so this is my only hope. Any help would be appreciated.

This is my code:

 
 # get 1000 samples with 10 scores each

scores <- rnorm(1000*10,100,25)
samples <- rep(1:1000,each=10)
my_df <- data.frame(samples,scores)

# get the means of the samples

sample_means <- my_df %>%
                group_by(samples) %>%
                summarise(means=mean(scores))

# make a histogram

 ggplot(sample_means, aes(x=means))+
  geom_histogram(color="white")+
  theme_classic()
 
 
 #mean of sample means 
 
meanofmeans <- sample_means[,2] %>%
                 summarise(meanofmeans=mean(means))

meanofmeans


sdofmeans <- sample_means[,2] %>%
                 summarise(sdofmeans=sd(means))

sdofmeans

Attached are screenshots of the results I am getting.

Thank you for your time.

I have no idea what im doing wrong ive downloaded the data and still cant get it work. please help!!!

I can't seem to install the packages on r cloud and R studio will not download on my laptop. I basically finished both labs in class but I can't seem to open them.