Hi have two questions regarding an t-test assignment i did.

Basically the null hypothesis was that if sample x2 differed 35 off the mean from sample x1 was it reject-able?

The mean of sample x is 395

The mean of sample ý is 435.

So the issue is that i think the nominator for the t-statistic would go like this:

(395-435)-35.

Since x_mean - y_mean - (difference in hypothesized mean) would be the general form.

But my teacher writes it like 435-395-35, swapping x and y, and i don't understand why.

Second questions is that he does a two tailed CI(confidence interval), but for a test in difference were sample y is greater then sample x isn't it enough to only look at the higher bound?

Basically the null hypothesis was that if sample x2 differed 35 off the mean from sample x1 was it reject-able?

The mean of sample x is 395

The mean of sample ý is 435.

So the issue is that i think the nominator for the t-statistic would go like this:

(395-435)-35.

Since x_mean - y_mean - (difference in hypothesized mean) would be the general form.

But my teacher writes it like 435-395-35, swapping x and y, and i don't understand why.

Second questions is that he does a two tailed CI(confidence interval), but for a test in difference were sample y is greater then sample x isn't it enough to only look at the higher bound?

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