Question

If we wish to carry out inference procedures on the mean of a normally distributed population where sigma is known, we a) Click for List - should use the distribution. b) Click for List Both the t distribution and the standard normal distribution have a median of O. c) Click for List For the t distribution, the mean and variance are always equal. d) Click for List The t distribution has more area in the tails than the standard normal distribution e) Click for List - Thet distribution has a greater variance than the standard normal distribution.

Answer 1

From the given information above,

a) FALSE we use z test if standard deviation known

b) TRUE. Median of both distribution is 0

c) FALSE

d) TRUE

e) TRUE

The P value is 0.0218

N Mean StDev SE Mean Sample 1 18 23.65 2.50 0.5893 2 Sample t Tutor Sample 2 20 25.62 3.28 0.7334 Observed difference (Sample 1 - Sample 2):-1.97 Standard Deviation of Difference : 0.9408 Unequal Variances DF: 35 95% Confidence Interval for the Difference (-3.8799,-0.0601 ) Test Statistic t = -2.094

b) 0.025<p value<0.05

c) There is sufficient evidence to reject the null hypothesis at the 5% level of significance but not at the 1% level of significance