Useby using we need write the answer
download.file("https://www.openintro.org/stat/data/ames.RData", destfile = "ames.RData")
load("ames.RData")
area <- ames$Gr.Liv.Area
price <- ames$SalePrice
I need how to Get a sample with a size of 100, and find the sample mean and sample standard deviation of price.
I want 95% Confidence Interval for the population mean price.
Did you make any assumption while using Z-value (1.96) for 5% significance level in part (b).
The believe is that the true population mean of price is equal to $180,000. Decide if this is true or not by using the confidence interval you created in part b.
Your real estate rep claims that the average price of the houses is greater than $170,000. Test this hypothesis by using test statistics and p-value. Test it at 10% significance level. Be precise in your explanations.
Use the data given in #7. Define the houses as "large" if the area is greater than 1600. Use the command for this purposes:
large = ifelse(area>1600,1,0)
a. Find how many houses in the category of large? (Hint: Use table() command.
b. Find the average price of "large houses" and "not large" houses by using tapply() command. (In the data, large is represented by 1; and not large is by 0 )
c. Are they different?
d. Find the standard deviation of "large house" by using tapply() function.