--- alias: user-guide-individuals-and-moving-range description: "This chart displays individual data points and moving ranges for process monitoring" --- # Individuals And Moving Range (X Rm) The following table lists the properties of the Individuals And Moving Range (X Rm) chart. | Property | Description | |-----------------------------------------------------|--------------------------------------------------------------------| | **Chart** | Individuals and Moving Range *(I-MR)* | | **Process observation types** | Variables | | **Process observations relationships** | Independent | | **Sample Size** | 1 | | **Distribution type** | Normal | | **Size of shift to detect** | Large (≥ 1.5σ) | | **Individuals (Indicator 1)** | $x$ |U | **Moving Range (Indicator 2)** | $r_k = Abs(x_{k+1}-x_k)$ | | **Mean** | $\mu = \overline{\overline{x}} = \frac{\sum{x_i}}{n}$ | | **Mean Range** | $\overline{MR} = \frac{\sum{MR_i}}{i-1}$ | | **Process Mean** | $\mu$ | | **Process Standard Deviation** | $\overline{MR} = \frac{\sum{MR_i}}{i-1}$
Note that the first data point does not have a $MR$
$\sigma = S_{mr} = \frac{\overline{MR}}{d_2(w)}$
Because we only support $w=2$, the $d_2(w)$ can be replaced by the constant `1,1284` | | **Individuals (Indicator 1) Centerline** | $\mu$ | | **Individuals (Indicator 1) Control Limits** | $UCL = \mu + 3 \sigma$
$LCL = \mu - 3 \sigma$| | **Moving Range (Indicator 2) Centerline** | $\overline{MR} = \sigma\cdot d_2(w)$ | | **Moving Range (Indicator 2) Control Limits** | $UCL = \overline{MR} + 3\sigma \cdot d_3(w)$
$LCL = max(\overline{R}_i + 3\sigma \cdot d_3(w);0)$
Where $w=2$| Table: Individuals and Moving Range chart properties