Are Snakes Left-Handed or Right-Handed? Sometimes a snake will coil, or curl up, so that its left side is pointing in. Sometimes a snake will coil so that its right side is pointing in. In the following experiment, several cottonmouth snakes were observed over a period of time. The observers recorded the proportion of time that each one of the snakes coiled to the left. Four different categories of snakes were observed: adult females (n = 15), adult males (n = 5), juvenile females (n = 5), and juvenile males (n = 5). Assume that the measure "proportion of left-handed coils" is normally distributed. The table below shows the proportion of left-handed coils that was recorded for each of the snakes: 0.582 0.585 0.550 0.554 0.609 Adult Females 0.545 0.544 0.600 0.638 0.656 0.600 0.696 0.424 0.493 0.491 Adult Males 0.563 0.556 0.522 0.541 0.395 Juvenile Females 0.512 0.556 0.565 0.417 0.429 Juvenile Males 0.486 0.492 0.475 0.464 0.493 1 The observers wanted to study the adult females first: A How many degrees of freedom are associated with the sample size of adult females? B Find the sample mean and sample standard deviation for the adult females. C Assuming that u = 0.5, calculate the T-statistic for the adult females. D What does this test statistic say about this sample of 15 adult females? (Hint: Think about how this statistic compares with the assumed population mean.) E What does this test statistic say about the coiling preferences of the population of adult females? 2 The observers then studied the three other samples that each contain data on five snakes. A "Each of the three samples has the same sample size. What are the appropriate degrees of freedom for each? B What are the mean and standard deviation of each of these three sample? C Calculate the T-statistics for each of these three groups. Assume a population mean of = 0.5. Complete the table below: Group Adult males Juvenile females Juvenile males T-Statistic