Statistics Final Part 3 Silva
False
TRUE OR FALSE A researcher wants to test the hypothesis that on average girls perform better on standardized tests than boys. Since it is true that some boys do better than girls and some girls do better than boys, the researcher must use a two tailed test.
False
TRUE OR FALSE A type 1 error is when a person fails to reject the null hypothesis by mistake.
false
TRUE OR FALSE As the confidence level decreases the confidence interval will get wider.
false
TRUE OR FALSE As the confidence level increases the margin of error will decrease.
True
TRUE OR FALSE As the sample size decreases the margin of error will increase.
True
TRUE OR FALSE As the sample size increases the confidence interval will get narrower.
False
TRUE OR FALSE As the sample size increases the confidence interval will get wider.
False
TRUE OR FALSE As the sample size increases the margin of error will increase.
False
TRUE OR FALSE If a distribution is normal, then it is not possible to randomly select a value that is more than 4 SD from the mean.
True
TRUE OR FALSE Test statistics help determine if the sample data is significant or not
False
TRUE OR FALSE The margin of error is how far one sample may differ from another sample.
false
TRUE OR FALSE The standard error and the margin of error are the same thing.
False
TRUE OR FALSE To limit the possibility of making a type 1 or type 2 error, we should get a small sample size
True
TRUE OR FALSE To limit the possibility of making a type 1 or type 2 error, we should have a small significance level
True
TRUE OR FALSE We use random assignment in experiments to create similar groups
FAlse
TRUE OR FALSE We use random assignment in observational studies to represent the population
False
TRUE OR FALSE We use random assignment in observational studies to represent the population
True
TRUE OR FALSE When computing confidence intervals for paired differences, only the difference values (x1 - x2) are used and not the original values of x1 and x2 to compute the mean and standard deviation.
Statistic
A number that describes sample data
Parameter
A number that describes the population
Census
Survey of the entire population
True
TRUE OR FALSE A P-value of 0.000003 tells us that the sample data was unlikely to happen by random chance.
False
TRUE OR FALSE If the sample size is increased and the standard deviation and confidence level stay the same, then the margin of error will also be increased.
True
TRUE OR FALSE P values help determine if the sample data is significant or not
True
TRUE OR FALSE A Chi-Square test for independence was done to see whether the type of salad dressing people order at a restaurant and the type of meat they order are independent or dependent. If the P-value was found to be 0.02, then at a 5% level of significance it can be concluded that dressing type and meat type are dependent.
False
TRUE OR FALSE A P-value of 0.442 tells us that the sample data was unlikely to happen by random chance.
True
TRUE OR FALSE A confidence interval represents the difference between two populations and both of the numbers in the confidence interval are negative. This means that group 1 is significantly less than group 2.
False
TRUE OR FALSE A confidence interval represents the difference between two populations and both of the numbers in the confidence interval are positive. This means that there is no significant difference between the groups.
false
TRUE OR FALSE A confidence interval represents the difference between two populations and the numbers in the confidence interval have opposite signs (1 positive and 1 negative). This means that group 1 is significantly greater than group 2.
False
TRUE OR FALSE A researcher is studying hours of sleep based on job type and also based on national origin to see if hours of sleep is independent of each of these. The researcher should use a 1-way ANOVA for this study.
Confidence Interval
Two numbers that we think the population value is in between
Random
When everyone has a chance to be a part of the sample