一家医院正在研究一种据称可以降低血压的新药。他们给一组患者服用新药,三小时后记录每位患者血压降低(或升高)的量。结果,以毫米汞柱(毫米汞柱)测量如下。
12 31 24 18 21 34 40 19 23 17 16
一)
画一个茎叶图来显示这些结果。
这些数据不是按顺序排列的,所以第一步是画一个粗略的图表。
所有值都是两位数字,因此将每个数字分开,以便第一个(十位)数字是一个干,第二个(单位)数字是一个叶。
|
降低血压 |
1 |
2 |
8 |
9 |
7 |
6 |
3. |
1 |
4 |
|
|
|
2 |
4 |
1 |
3. |
|
|
4 |
0 |
|
|
|
|
对于最后的图表,将茎叶按顺序排列,并添加一个键。
|
降低血压 |
1 |
2 |
6 |
7 |
8 |
9 |
2 |
1 |
3. |
4 |
|
|
3. |
1 |
4 |
|
|
|
4 |
0 |
|
|
|
|
关键:1|2表示血压降低12 mmHG
b)
使用你的茎叶图找到血压降低的中位数和四分位范围。
对于中位数,将最高和最低的数字交叉,直到我们在中间相遇。
|
降低血压 |
1 |
2{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线2" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
6{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线6" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
7{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线7" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
8{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="上对角线8" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
9{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线9" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
2 |
1{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="圈括粗体1" style="vertical-align:-11px;height:32px;width:23px" loading="lazy"> |
3{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角击球3" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
4{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线4" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
|
|
3. |
1{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线击1" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
4{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线4" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
|
|
|
4 |
0{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线0" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
|
|
|
|
中位数是2茎中1的叶子。
中位数= 21
对数据的下半部分和上半部分重复,以找到下四分位数和上四分位数。
|
降低血压 |
1 |
2{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线2" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
6{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线6" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
7{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="圈括粗体7" style="vertical-align:-11px;height:32px;width:23px" loading="lazy"> |
8{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="上对角线8" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
9{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线9" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
2 |
1{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="圈括粗体1" style="vertical-align:-11px;height:32px;width:23px" loading="lazy"> |
3{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角击球3" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
4{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线4" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
|
|
3. |
1{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="圈括粗体1" style="vertical-align:-11px;height:32px;width:23px" loading="lazy"> |
4{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线4" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
|
|
|
4 |
0{"language":"en","fontFamily":"Times New Roman","fontSize":"18","autoformat":true}" class="Wirisformula" role="math" alt="向上对角线0" style="vertical-align:-6px;height:22px;width:10px" loading="lazy"> |
|
|
|
|
LQ是1的茎上7的叶子;Lq = 17。UQ是3茎中1的叶子;Uq = 31。
这个问题问的是四分位范围。
Iqr = uq - lq = 31 - 17 = 14
中位数= 21毫米汞柱
四分位间距= 14 mmHG