# e-book 5 Steps to a 5 AP Psychology, 2008-2009 Edition

Because a and c are the more rational responses, they are less likely to have been the way most callers would have responded. From Chapter 8 A random sample from a population is one in which every member of the population is equally likely to selected. A simple random sample is one in which every sample of a given size is equally likely to be selected. A sample can be random sample without being a simple random sample. From Chapter 6 The teachers are interested in showing that the average teacher salary is low. Because the mean is not resistant, it is pulled in the direction of the few higher salaries and, hence, would be higher than the median, which is not affected by a few extreme values.

The teachers would choose the median. The mode, standard deviation, and range tell you nothing about the average salary. Thus, 0. Heads Observed 0 10 0. In a chi-square goodness-of-fit test, the number of degrees of freedom equals one less than the number of possible outcomes. From Chapter 6 There are terms, so the median is located at the 56th position in an ordered list of terms. From the counts given, the median must be in the interval whose midpoint is 8. Because the intervals are each of width 2, the class interval for the interval whose midpoint is 8 must be 7, 9.

From Chapter 8 In an experiment, the researcher imposes some sort of treatment on the subjects of the study. Both experiments and observational studies can be conducted on human and nonhuman units; there should be randomization to groups in both to the extent possible; they can both be double blind. However, R-sq is the square of the correlation coefficient.

From Chapter 14 There are 81 observations total, 27 observations in the second column, 26 observations in the first row. From Chapter 14 I is true. From Chapter 7 An influential point is a point whose removal will have a marked effect on a statistical calculation.

For a one-sided test and 13 degrees of freedom, 0. From Chapter 8 Numbers of concern are 1, 2, 3, 4, 5, 6. We ignore the rest. We also ignore repeats. Reading from the left, the first three numbers we encounter for our subjects are 1, 3, and 5. They are in the treatment group, so numbers 2, 4, and 6 are in the control group. You might be concerned that the three women were selected and that, somehow, that makes the drawing nonrandom.

## 5 Steps to a 5 AP Statistics, Edition

However, drawing their three numbers had exactly the same probability of occurrence as any other group of three numbers from the six. From Chapter 10 The statement in e describes the random variable for a geometric setting. In a binomial setting, the random variable of interest is the number count of successes in the fixed number of trials. A necessary condition for this to be true is that the variables X and Y are independent. From Chapter 14 Because 0 is not in the interval 0. This implies a non-zero correlation coefficient and the existence of a linear relationship between the two variables.

From Chapter 10 This is a geometric setting independent trials, each succeeding or failing with the same probability. That way, we are controlling for the possible confounding effects of the river. Hence the answer is c. If you answered e , be careful of confusing the treatment variable with the blocking variable.

### Kundrecensioner

Note that if Grumpy had been 4 points above the mean on the first test and Dopey 5 points above the mean on the second, then Dopey would have done slightly better than Grumpy. N If you got an answer of 0. For each additional year of age, the height in cm is predicted to increase by 6. The prediction would probably be too small. It is an observational study. The researcher made no attempt to impose a treatment on the subjects in the study. The hired person simply observed and recorded behavior.

Without that you are unable to judge how much sampling variability there might have been. The population at that Scorebucks might differ in some significant way from the patrons at other Scorebucks around the city and there are many, many of them. It might have been different on a different day or during a different time of the day. You would conduct the study at multiple Scorebucks, possibly blocking by location if you believe that might make a difference i. You would observe at different times of the day and on different days.

You would make sure that the total sample size was large enough to control for sampling variability. Determine Your Test Readiness 4. Let p1 be the true proportion who planned to vote for Buffy before her remarks. Let p2 be the true proportion who plan to vote for Buffy after her remarks. The problem tells us that the samples are random samples. The data are paired, so we will use a matched pairs test. We have evidence that, in identical twins reared apart, that the better educated twin is likely to have the higher IQ score. We are told that the 20 cans of paint have been randomly selected.

It is reasonable to assume that a sample of this size is small relative to the total population of such cans. A box-plot of the data shows no significant departures from normality. Because minutes is in this interval, we would not consider an average drying time of minutes for the population from which this sample was drawn to be unusual. For the two-sided test, we concluded that we did not have evidence to reject the claim of the manufacturer. Use complete sentences. Don't ramble. Your own test-taking history and these tips should help you demonstrate what you know and you know a lot on the exam.

## Ap physics 1 essentials

The tips in this section are of a general nature—they apply to taking tests in general as well as to both multiple-choice and free-response type questions. Look over the entire exam first, whichever part you are working on. With the exception of, maybe, Question 1 in each section, the questions are not presented in order of difficulty.

Find and do the easy questions first. Remember that you have an average of slightly more than two minutes each for each multiple-choice question, 12—13 minutes for Questions 1—5 of the free-response section, and 25—30 minutes for the investigative task. Some questions are very short and will give you extra time to spend on the more difficult questions.