In a simple linear regression you are told that the estimate of the slope coefficient was 0.9 and that the "t-statistic" for testing whether the slope parameter was unity or not was -3.8. What is the estimated standard error for the estimated slope coefficient?

20 out of 25 cars are red, with a past probability of 0.28?

To calculate the estimated standard error for the estimated slope coefficient in a simple linear regression, you would need two pieces of information: the estimate of the slope coefficient and the t-statistic.

The estimated standard error (SE) of the estimated slope coefficient can be calculated using the formula:

SE = estimated standard deviation / sqrt(sample size)

In this case, the estimated standard deviation is not given, but we can use the t-statistic and the degrees of freedom to calculate it.

The t-statistic is calculated by dividing the estimated slope coefficient by its standard error:

t = estimated slope coefficient / SE

Rearranging the formula, we can solve for the standard error:

SE = estimated slope coefficient / t

Plugging in the given numbers, the estimated slope coefficient is 0.9 and the t-statistic is -3.8:

SE = 0.9 / (-3.8)

Now we can calculate the estimated standard error:

SE ≈ -0.237

Therefore, the estimated standard error for the estimated slope coefficient is approximately -0.237.