Normal Distribution 1
This is the name of a normal distribution with a mean of 0 and a standard deviation of 1.
Half the area under the normal distribution curve equals ___.
In the equation for converting to Z for sampling distribution, X̄ refers to ______.
the sample mean
"H0" refers to the _________.
null hypothesis
When conducting a hypothesis test, the first step is to set up your ____ and ____ hypotheses.
null; alternative
You need to find the probability of a value lower than X, when X is below the mean. You look in Column ___ of your Z table.
If you want to find the area under the normal distribution curve between Z and the mean, you should look in column __ of the Z-table.
B
If I take infinite random samples over 30 people in the city of Milwaukee and calculate the mean age for each sample, the distribution of sample means will be _____.
normal
If the alternative hypothesis is that the population mean is less than, the null hypothesis is that the population mean is:
greater than or equal to
You are asked to calculate X for the 61st percentile. You look in your Z-table for the number closest to ___ in Column ___, and then find your Z-value in Column A.
.39; C
You need to find the probability between a range of Z values, with one Z value below the mean and the other above the mean. You calculate the probability by adding Column ___ for the lower value to Column ___ for the higher value.
B; B
You are asked to find the probability that the sample mean for a randomly drawn sample of people is greater than 550. If the population mean is 443.2, then you should look in Column __ of the Z-table to find your answer.
C
In order to determine which hypothesis is more reasonable, the researcher imagines a world where ____ is true and calculates the probability of getting her sample results.
the null hypothesis
A school claims that the mean standardized test score for their students is 78.2. A researcher believes that it is not 78.2. His alternative hypothesis is that the ______ for students' standardized test scores is not 78.2.
population mean
You need to find the probability for a range of values, where both values are above the mean. You can find this by taking Column ___ for the larger value - Column ___ for the smaller value.
B; B
400.04
You have a normally distributed numeric continuous variable with a mean of 600 and a standard deviation of 200. You need to find the probability that a random sample of 100 people has a mean of greater than 640.
P (X̄>640) = P (Z>___) (Include two decimal places.)
2.00
A hospital report states that mean out-of-pocket cost to patients for outpatient services is $950. A researcher believes that it is higher. The null hypothesis is:
The population mean cost for outpatient services is less than or equal to $950.
A researcher finds a p-value of .0201. If their alpha is .01, then they should ____ the null hypothesis.
fail to reject
You have a normally distributed numeric continuous variable with a mean of 50 and a standard deviation of 10. P (X>55) = P (Z>___)
.5
You have a normally distributed numeric continuous variable. The probability that Z is less than .81 = _____.
You have a normally distributed numeric continuous variable with a mean of 250 and a standard deviation of 60. ______ is the probability that a random sample of 36 people has a mean of greater than 240. (Include four decimal places)
.8413
A researcher finds that there is a low probability of getting her sample results in a world where the ______ hypothesis is true. Therefore, she states that she ______ the ______ hypothesis.
null; rejects; null
null; null; fail to reject