Question

,,1-The sampling distribution of the mean is...............?

2- The expected value of a random variable corresponds to the notion of the ________ of a sample.?

3- A negative correlation coefficient indicates a linear relationship between variables where one variable increases as the other increases. Is T or F?

4- If a variable is removed from the regression model when the t-statistic is lesser than 1, ________.?

5-  If we sample with replacement from a finite population, the sampling distribution of the sample proportion follows the ...........?

binomial distribution

uniform distribution

normal distribution

chi-square distribution. which one is correct?

6- Categorical variables are included in regression analysis by ?

7- The cumulative relative frequency represents the proportion of the total sample that falls at or below the upper limit value. Is T or F?

8- A chi-square statistic is the sum of the squares of the differences between observed frequency and expected frequency divided by the expected frequency in each cell.   Is T or F?  

9- It is not possible to manipulate statistical displays to suit the creator's conclusions. Is T or F?  

10-

In a probability mass function, the probability of each outcome must be less than zero. Is T or F?  

Answer 1

1-The sampling distribution of the mean is the probability distribution of sample mean when sample is drwan from the population.

2-The expected value of a random variable corresponds to the notion of the ___mean_____ of a sample

3- A negative correlation coefficient indicates a linear relationship between variables where one variable increases as the other increases - TRUE

4- If a variable is removed from the regression model when the t-statistic is lesser than 1,  then, we can say that variable is not important when the other variables are present in the model

5-  If we sample with replacement from a finite population, the sampling distribution of the sample proportion follows the Normal distribution. - By central limit theorem

6- Categorical variables are included in regression analysis by creating dummy variables for each category of the variable.

7- The cumulative relative frequency represents the proportion of the total sample that falls at or below the upper limit value - TRUE

8- A chi-square statistic is the sum of the squares of the differences between observed frequency and expected frequency divided by the expected frequency in each cell - TRUE

9- It is not possible to manipulate statistical displays to suit the creator's conclusions - FALSE, an example is : Obtaining a p-value of 0.499 and saying that it is less than 0.05 and claim that null hypothesis is rejected.

10- In a probability mass function, the probability of each outcome must be less than zero. - FALSE, a probability can't be less than zero.