Hypothesis Tests Flashcards
An assumption made about the value of a population parameter is called a
hypothesis
In hypothesis testing if the null hypothesis is rejected,
the alternative hypothesis is true
The average monthly rent for one-bedroom apartments in Chattanooga has been $700. Because of the downturn in the real estate market, it is believed that there has been a decrease in the average rental. The correct hypotheses to be tested are
H0: mean >/= 700 Ha: mean
The average hourly wage of computer programmers with 2 years of experience has been $21.80. Because of high demand for computer programmers, it is believed there has been a significant increase in the average wage of computer programmers. To test whether or not there has been an increase, the correct hypotheses to be tested are
H0: mean 21.80
The probability of committing a Type I error when the null hypothesis is true is
the Level of Significance
The level of significance is the
maximum allowable probability of Type I error
The error of rejecting a true null hypothesis is
a Type I error
The level of significance
is (1 - confidence level)
The probability of making a Type I error is denoted by
alpha
In the hypothesis testing procedure, alpha is
the level of significance
If a hypothesis is rejected at the 5% level of significance, it
may be rejected or not rejected at the 1% level
If a hypothesis is rejected at 95% confidence, it
will always be rejected at 90% confidence
For a lower tail test, the p-value is the probability of obtaining a value for the test statistic
at least as small as that provided by the sample
The p-value
is a probability
When the following hypotheses are being tested at a level of significance of alpha
H0: mean >/= 500 Ha: mean < 500
the null hypothesis will be rejected if the p-value is
</= alpha
In order to test the following hypotheses at an alpha level of significance H0: mean 800
the null hypothesis will be rejected if the test statistic Z is
> /= Za
As the test statistic becomes larger, the p-value
gets smaller
For a lower bounds one-tailed test, the test statistic z is determined to be zero. The p-value for this test is
+0.5
For a one-tailed test (lower tail) at 93.7% confidence, Z =
-1.53
A two-tailed test is performed at 95% confidence. The p-value is determined to be 0.09. The null hypothesis
should not be rejected
For a one-tailed test (lower tail) at 89.8% confidence, Z =
-1.27
For a one-tailed hypothesis test (upper tail) the p-value is computed to be 0.034. If the test is being conducted at 95% confidence, the null hypothesis
is rejected
In a one-tailed hypothesis test (lower tail) the test statistic is determined to be -2. The p-value for this test is
0.0228
In a two-tailed hypothesis test situation, the test statistic is determined to be t = -2.692. The sample size has been 45. The p-value for this test is
+0.01
For a two-tailed test, a sample of 20 at 80% confidence, t =
1.328
For a one-tailed test (lower tail), a sample size of 10 at 90% confidence, t =
-1.383
For a one-tailed test (lower tail) with 22 degrees of freedom at 95% confidence, the value of t =
-1.717
